Chapter XVII: Introduction (15)

_Pochazia australis_ measures about ¾ of an inch across the short broad fore wings, which are margined and irregularly barred with chocolate brown; the head is short and rounded in front. Melichar, in his “Monographie der Ricaniiden, Wien,” 1898, places _P. australis_ in the Genus _Scolypopa_. The larva is a green wedge-shaped little creature clothed at the tip of the abdomen with a bunch of white filaments. It is a very common insect with a wide range. Sometimes it is a pest on passion vines; the eggs are laid in the slender tendrils, and the larvae suck up the sap of the stalks. Another species is common among the foliage of the silky oak (_Grevillia robusta_) in Southern Queensland.

_Achilus flammeus_ has the body and wings of a bright red colour, with the small head showing prominently in front: the broadly rounded opaque elytra and wings cover the short body. It measures about an inch across the outspread wings. Nothing is known about its habits or life history, but in the summer evenings it sometimes comes flying towards the light, and can be found on the windows.

The Genus _Poeciloptera_ contains a number of small, short broad-winged forms. Donovan figures _Poeciloptera modesta_, which has pink fore wings, each marked with two small red spots, and the hind wings have a pale bluish tint.

_Prolepta dilatata_ is a typical, dull reddish-brown fulgorid, measuring nearly an inch from the tip of the long slender head to the extremities of the folded tegmina which are broadest across the tips: and the slender prolonged forehead is over two lines in length. This insect was described from W. Australia, but it has a wide range and can be collected about Sydney. _P. obscurata_ is about the same size, more rugose in structure, and with markings of dark brown; the markings on the somewhat opaque wings are more distinct, striated and irregular than in _P. dilatata_: it can also be easily recognised by the shorter and thicker process on the forehead. It has a wide range over Australia.

The Genus _Eurybrachys_ contains a number of short, dark brown insects with broad rounded heads; they run about on the trunks of trees, jumping at the least alarm. _Eurybrachys leucostigma_ is a very stout, broad, dull brown insect, about ¾ of an inch across the outspread wings. Some 16 species are described from all parts of Australia. The members of the Genera _Ledra_ and _Stenocotis_ are broad elongate insects with the front of the head spade-shaped, and the convex body tapers to a sharp point. Their larvae are almost as flat as a bit of paper. _Stenocotis australis_ is about ¾ of an inch in length, and of a dull brown tint.

Family 5. Leaf-Hoppers.

JASSIDAE.

These insects are minute froghopper-like forms with the head rounded in front, and with the body tapering towards the tips of the tegmina. The head is large, with the oval or rounded eyes projecting on the sides, and with a pair of ocelli situated on the front margin. The antennae, bristle-like, of considerable length, are each composed of two short cylindrical basal joints with a thread-like terminal portion, and are placed in front and below the eyes. The legs are long, well adapted for jumping (their chief means of progression); and the tibiae of the hind pair are thickly clothed with stout spines.

Though these insects are very small, many species appear upon crops and herbage in such immense numbers that they often do a great deal of damage, and are very interesting from an economic standpoint. In Japan, for instance, there are several species very serious pests in the rice fields; while in North America _Erythroneura vitis_ is a well-known pest upon the foliage of vines.

They are abundant on the low scrub and grass lands in this country in favourable localities, and may be easily collected with a sweeping net, or by shaking the bushes over an open umbrella; yet, probably on account of their small size and retiring habits, few specimens are to be found even in our Museum collections.

The sugar-cane hopper, _Perkinsiella saccharicida_, a native of Queensland, is a dull brownish yellow hopper with a dark parallel stripe down the centre of the basal portions of the tegmina; it measures a ¼ of an inch in length. Kirkaldy described it from Hawaii, where it has been introduced, and is a serious pest to the sugar-cane.

A very pretty little unidentified species, bright red and yellow, with the fore wings marked with dark brown, is common upon the broad soft leaves of _Eucalyptus robusta_, where the curious little larvae rest in families of three or four; each is enveloped in white filaments which proceed from round the tip of the abdomen. The larvae of another species have been observed to form large colonies on the surface of the leaves of low eucalyptus bushes on the hills near Capertee N.S.W. They suck up the sap, discolouring the centre of the leaves; each exudes a globule of liquid from the tip of the abdomen, which they drag out into thin threads with their hind legs, to form a spider-web-like covering over their bodies, and this web dries soon after the leaves are gathered.

Family 6. Lerp Insects.

PSYLLIDAE.

These are small homoptera, in appearance suggesting miniature cicadas. The head is generally broader than long, sometimes deflected and with large eyes; the ocelli are three in number, the lateral ones situated on the summit of the head close to the hind margins of the eyes, and the central one at the apex of the median suture. The antennae are each composed of ten joints, the first two shorter and thicker than the following ones, and the terminal joint surmounted with two short bristles. The thorax is broad, with well developed tegmina and wings, and like the aphids both pairs might properly be called wings. The venation is simple, constant, and useful in the work of classification. They are formed for jumping, with a spine-like process on the coxa of each hind leg, and the apex of the tibiae of the hind legs furnished with a row of short fine spines. The tarsi are two jointed, terminating in a pair of large claws.

Showing the structure and venation of the wings.

1_a_, Face lobes; 2_a_, prothorax; 3_a_,
mesanotum; 4_a_, dorsulum; 5_a_, scutellum, tegmina;
1_b_, costal nervure; 2_b_, primary stalk; 3_b_,
clavus; 4_b_, clavical suture; 5_b_, stalk of
sub-costa; 6_a_, stalk of cubitus; 7_b_, sub-costa;
8_b_, lower branch of cubitus; 9_b_, upper branch of
cubitus; 10_b_, lower fork of lower cubitus; 11_b_,
stigma; 12_b_, upper fork of the lower branch of cubitus;
13_b_, radius; 14_b_, lower fork of upper cubitus;
15_b_, upper fork of upper cubitus.

3, Genitalia ♂; 4, Genitalia ♀; 5, Head of _Spondyliaspis
eucalypti_, showing face lobes.

(Pro. Linn. Soc. N.S.W.)]

The female lays her eggs in clusters on the twigs or foliage, from which the curious, little, large-headed larvae emerge, and, after undergoing a series of moults during which they develop large wing-pads on the shoulders and more joints in the antennae, they finally come forth, perfect four-winged insects. They take their family name from _Psylla_, a flea, given them by Linnaeus in reference to their jumping powers, and their popular name of “Lerp Insects,” from the habit of the larvae of many species of forming “lerp scales,” shell-like protective coverings formed from exudations from the insects. Other species cover themselves with flocculent matter after the manner of mealy bugs; and yet another group form regular oval or rounded galls on the foliage. They are found in most of the warmer parts of the world, and are very numerous in Australia, where they seem to take the place of the APHIDAE to a certain extent; they are readily collected in all stages of growth upon their food plant, and can be easily bred.

The Sugar lerp, _Psylla eucalypti_, whose larvae cover the leaves of several species of gum trees with their white woolly shells, was described by Dobson from Tasmania (Pro. Royal Soc. Van Diemen’s Land, 1851). It is a slender little green creature with very long face lobes, and, when crawling about, turns the tip of its body upwards, so that it looks as if it were walking on its head. It is now placed in the Genus _Spondyliaspis_.

In the same year (1851) Walker published his Homoptera (Cat. Brit. Museum) in which he recorded 5 species, all from Tasmania; and it was not until 1898 that they were again noticed when Maskell described 3 species from Australia (Trans. N. Zealand Inst.); and Schwarz defined another (Pro. Ent. Soc. Washington) in 1897. Between the years 1900 and 1903 I contributed three papers (Pro. Linn. Soc. N.S.W.) monographing our species, in which 64 new species are added to our fauna. I followed Low in the classification of the sub-families, adding Scott’s fifth division for those with small heads and no face lobes.

In the LIVIINAE, the front of the head is not produced into face lobes; the stalk of the cubitus is either shorter, as long as, or longer than the lower branch of the cubitus. _Crewiis longipennis_ is of a general bright red tint, and is ¼ of an inch in length; it ranges from Tasmania to the North of New South Wales. The larva forms a rounded pale yellow lerp covered with fine woolly filaments upon the leaves of gum trees. _Lasiopsylla rotundipennis_ forms a large, flattened, irregularly rounded white scale on the foliage of _Eucalyptus melliodora_, under which the flattened, pale green larva hides.

The Sub-family APHALARINAE contains a number of small species, and the head is produced in front into face lobes, with the stalk of the cubitus as long as or longer than the stalk of the sub-costa. They usually form lerp scales; but some are naked, or clothed with soft white woolly filaments.

Several species of the Genus _Spondyliaspis_ belong to this group; all of them form “sugar lerp scales,” often encrusting all the foliage of the young gum trees, and are so abundant that in the Mallee scrub country in Victoria and S. Australia the blacks used to collect and eat it in quantities, and had a regular “manna harvest.” _Cardiaspis artifex_ is a short, reddish yellow insect, the larvae of which form beautiful barred shell-like lerps, marked with red and yellow to look like delicate fretwork, upon the leaves of _Eucalyptus robusta_. _C. tetrix_ is a pretty pink and grey species found in the Adelong district, N.S.W. The larva constructs a most remarkable cage of fine red bars, not unlike a lady’s hair net, beneath which the larva crawls about freely like a bird in a cage. _Rhinocola corniculata_ often covers the leaves of different eucalypts with its elongate, opaque, horny, yellow lerps. The test is not unlike that of a large _Mytilaspis_ scale, but is open at the broad end through which the little larva can creep in and out. It ranges from New South Wales to Western Australia. _R. eucalypti_ is a very tiny, little, dark brown psylla, the larvae of which cluster at the tips of the foliage of young blue gums (_Eucalyptus globulus_), and cover themselves with threads of white flocculent matter. It was described by Maskell from New Zealand, but is common both in Tasmania and Australia: it has also been introduced into Africa on the same eucalypt.

The larvae of the Genus _Thea_ are curious, broad, flattened creatures, with hard integument. They hide under the dead bark on the trunks of the white stemmed gums, spreading their white woolly secretion around them; the ants look after them, and probably protect them from many enemies in return for the “honey dew,” of which secretion the ants are very fond. _Thea opaca_ is of a general reddish pink colour mottled with brown and black; the wings are transparent, with a dark stigma on the fore wing.

The members of the Sub-family PSYLLINAE have the same well-defined conical face lobes, but the stalk of the cubitus is shorter than the stalk of the sub-costa. The larvae may be quite naked, but most of them produce woolly filaments more or less covering them, and form no true lerp scales or galls. The typical Genus _Psylla_ comprises a number of usually small and somewhat stouter insects, many of which cluster in swarms like aphids upon the foliage of wattles and other trees. The eggs, larvae, pupae, and perfect insects may be found on the same twigs. _Psylla acaciae-decurrentis_ is a slender, dark-winged insect remarkable for the length of its slender antennae; it is common upon the black wattle in early summer. _P. acaciae-baileyanae_ is a much smaller yellow species with mottled wings that often swarms over the cultivated “Cootamundra wattle,” and is reported to have destroyed all the flower-buds of this wattle in the neighbourhood of Melbourne in 1905. _P. capparis_ is a mottled winged species that frequents the foliage of _Capparis mitchelli_ in the western scrubs: _P. schizoneurodes_ infests the twigs of the allied “Warrior Bush”; the larvae are covered with flocculent matter and have a globule of liquid substance at the tip of the abdomen; when massed together they look much like “woolly blight” on the apple trees. _P. sterculiae_ is a small brownish species, found upon the twigs of the Kurrajong, and has a wide range over New South Wales.

The Kurrajong Twig Psylla.

(“Agricultural Gazette,” N.S.W.)]

Two very curious species are found upon the thick fleshy leaves of our native figs, and one, _Mycopsylla fici_, lays her eggs upon the foliage, the squat grey larvae burying their beaks in the leaf cause a flow of milky sap, under which they hide in small colonies, and when ready to emerge crawl from beneath the viscid mass. Where numerous, they cover the foliage with these sticky patches, and cause the leaves to fall. The perfect psylla is a handsome, dark-coloured insect with long antennae and ample transparent wings.

The Star-psylla found on the surface of the leaves of the
Kurrajong.

(“Agricultural Gazette,” N.S.W.)]

Sub-family TRIOZINAE. The cubitus of the wing has no stalk, the veins forking directly from its junction with the sub-costa. All our species, with one exception, come into the typical Genus _Trioza_: many of them are gall makers in the larval state, others are naked and cling to the under surface of twigs and leaves. The larvae of the gall-makers are broad, oval, flattened creatures, covered with a mealy secretion, the outer margin of the dorsal shield in each case being fringed with fine regular ciliae. Most of the perfect insects are thickset; they range from chestnut brown to reddish yellow; and have clear transparent wings. _Trioza carnosa_ makes a large, oval, fleshy, brightly tinted gall with an irregular opening at the summit, often covering and aborting the foliage of eucalypts about Sydney. The larva of _T. eucalypti_ forms a rounded, hard, woody gall upon the leaves, without any opening on either side until the gall contracts and splits open, when the full grown pupa emerges. _T. casuarinae_ is a very pretty little psylla with dark-barred wings, and its curious naked fish-like larva clings to the slender foliage of the she-oak (_Casuarina_). _T. banksiae_ has a tiny, naked, yellow larva covered with silvery down; it is a rare insect found on the under surface of the honeysuckle leaves. Nearly all these species have been collected within a day’s journey from Sydney, but have a wide range on the eastern coast.

The Sub-family PRIONOCNEMINAE was formed by Scott for Walker’s Genus _Tyora_, in which I have placed two species. _Tyora sterculiae_ is a pale green, aphid-like psylla, with long antennae and large transparent wings. The larvae cluster together on the leaves of the Kurrajong, forming white patches over the foliage, and each larva throws out slender white threads, fringing the tip of the abdomen and radiating about the body. _T. hibisci_ is a delicate pale green insect which has been taken on the foliage of _Hisbiscus tiliaceus_, about Brisbane, Queensland, and also on a creeper on the Tweed River, New South Wales.

Family 7. Aphids or Plant Lice.

APHIDAE.

These destructive little creatures are well known to gardeners under different names, such as “smother or green-fly,” “plant lice,” or “blight.” This family contains one of the most destructive and widespread pests that ever attacked cultivated plants, namely the vine louse (_Phylloxera vastatrix_), which has destroyed millions of pounds’ worth of vines, and has followed its host all over the world. Aphids are all small soft-bodied creatures, green, black, or yellow in colour; and at least ten introduced species are to be commonly found in our gardens and fields; but as far as I know, no indigenous aphid is recorded in Australia.

The life history of these insects is very complex; the winter eggs or larvae lie dormant during the cold season in crevices on the trunks, or hidden underground on the roots of their host plants; but as the warm weather approaches they crawl up the trunks, cluster round the opening leaf buds, and sticking their sharp beaks into the tissue, suck up the sap. These give birth to living larvae which grow very rapidly, and in turn (though virgin females) bring forth fresh broods of live larvae that in the course of several generations develop two pairs of large transparent wings, and consist usually of both sexes, though in some species the males are wanting. The last generation fly away in swarms but before dying deposit eggs which carry on the cycle of their life into the next summer.

The wingless forms are short, stout, rounded creatures with small, slightly lobed heads, and rather stout 3 to 7 jointed antennae; the legs are well-developed with two-jointed feet. The abdomen often swells out into a flask-like shape; it is furnished on the 5th segment with a pair of cylindrical tubes called siphons, through which it discharges a sweet secretion known as “honey dew”; this liquid is often ejected in such quantities on aphis-infested plants that it covers the foliage, and attracts the ants, which come and lick up the globules of honey-dew on the tips of the siphons, and even caress the aphis with their antennae; and therefore in popular works these insects are often described as “ants’ cows.”

The Rose Aphis of the garden.

1, Rose buds infested with aphis; 2, larva; 3, winged female
aphis.

(“Agricultural Gazette,” N.S.W.)]

The American Peach Aphis (introduced).

(“Agricultural Gazette,” N.S.W.)]

Among the introduced species common in Australia is the Cabbage Aphis, _Aphis brassicae_, a dull green insect covered with a floury exudation; it is one of the greatest pests that the cabbage-growers have to deal with, and is always most troublesome in dry weather. The Rose Aphis, _Siphonophora rosae_, is a pale green species appearing in the spring on the young buds of the roses, but seldom doing very serious damage. The Woolly Aphis, _Schizoneura lanigera_, common both on the roots and branches of apple trees, is found in most of our old orchards; the dull blue aphids cluster together in colonies with their beaks buried deeply in the bark, and the clusters become covered with a mass of soft white flocculent exudation, hiding them from view. From the irritation to the plant tissue caused by their presence large galls or excrescences appear all over the branches. The Peach Aphis, _A. persicae-niger_, is another common orchard pest which winters on the roots of the peach trees: in early summer they commence to spread, and if neglected do a great deal of damage to the leaf and flower buds.

The chief work dealing with the systematic classification of plant lice is Buckton’s “Monograph of the British Aphidae,” published by the Roy. Society, London 1881. A number of new species have been described since by American entomologists in bulletins on Economic Zoology.

Family 8. Snow-Flies.

ALEURODIDAE.

These are all very small delicate creatures; both sexes are furnished with two pairs of broad rounded wings with simple parallel veins, and are usually thickly covered with a mealy white dust from which they take their popular name of “Snow-Flies.” The head is broad, furnished with a three-jointed beak enclosing setae; seven-jointed antennae; and large reniform eyes, with an ocellus on either side above the eyes. The thorax is broad and the abdomen soft and rounded. The tarsi are two-jointed terminating in two claws at the extremities.

The female lays her eggs in clusters on the under surface of the leaves, where the young larvae later on form regular oval, glassy tests of various colours, enclosed in which they feed and finally pupate. The adult insects have their short broad wings slightly expanded, and cluster together in threes and fours: but the moment their food plant is touched they fly out in a little cloud. They can, like the scale insects, be very easily introduced into a new country with their food plant, and several species, like _Aleurodes vaporariorum_ described by Westwood from Europe, have a wide range over America and this continent.

The snow-flies are well represented in Australia, and several species do a considerable amount of damage to native shrubs, but on account of their delicate structure and small size they are difficult to collect, and harder to preserve when collected; if mounted on card they dry up, with nothing to determine them from but the wings, which have very few distinctive characters. The most satisfactory method of preserving them, is to drop the live insects into oil of cloves on a micro slip, when they usually open their wings and legs, and then make, with a little care, very fine objects when mounted in balsam; at times, however, the floury covering floats off the wings and body and sometimes clouds the mount.

Maskell has described 8 species from Australia (Trans. N. Zealand Inst. 1896); most of these descriptions, however, were based upon the larval tests or scales (and not the adult insects) which had been sent to him under the idea that they were scale insects; so that whoever takes up the study of snow-flies will have to breed them out, to be sure of the identity of his species. _Aleurodes styphelia_ forms a flattened, oval, black test fringed with white waxy tubes almost as long as the encircled larva, scattered about over the leaves of _Styphelia richei_, a common scrub bush about Sydney. _Aleurodes t-signata_ forms a spiny black test; and with a second undetermined pale yellow species without a marginal fringe, is found about Sydney on the foliage of _Acacia longifolia_. Another species, _A. banksiae_, is found upon both the honeysuckle (_Banksia_) and the bottle brush (_Callistemon_).

In Maskell’s paper, which is an important contribution to the study of these small but very interesting insects, he lists 65 known species belonging to the typical Genus _Aleurodes_; some have since been described from America, of which a few have been placed in the Genus _Aleurodicus_, formed by Douglas for those with a distal and basal branch on both wings.

Family 9. Scale Insects.

COCCIDAE.

These insects take their popular name of scale insects from the habit that many of the typical species have of protecting themselves, after they have settled down on their food plant, by forming a shield or scale over their backs under which they feed and produce their eggs or living larvae. To form the scale the moulted larval skin, called the pellicle, becomes a nucleus in the first place, round which exudations are added until the scale insect ceases growing.

The larvae are pale yellow, pink, or dull-red coloured little creatures, oval or shield-shape in form, usually fringed round the margins of the body with fine filaments, which are often long upon the somewhat thickened irregularly-jointed antennae and form longer setae upon the tip of the abdomen. They have distinct black eyes, well-developed legs; the mouth is pointed and beak-like. At this stage of their existence the sexes do not differ in outward appearance, but when they attach themselves to their food plant the males and females of the same species often construct scales of very dissimilar form; while in others the male scales are simply more elongate than those of the female.

The male coccid is a delicate fragile little creature, usually microscopic in size, so that, unless bred out in confinement from scale-infested foliage, they are seldom seen. He has a well defined head rounded behind, furnished with moderately long antennae composed of thickened irregularly-jointed segments fringed and surmounted with fine filaments. The globular black eyes stand out on the sides of the head, but the mouth is aborted so that it cannot feed. The thorax, lobed on the dorsal surface, is furnished with a pair of rounded wings each with a simple central nervure, but he can fly well in spite of their delicate structure. The slender legs are simple, terminating in rudimentary hooks; the elongated abdomen is distinctly segmented and furnished at the extremity with a pair of long slender white filaments. This period of his existence is short: thousands of them perish very soon after they leave their scale, and the survivors as soon as they have impregnated the female die.

The female coccid as soon as she settles down to suck up the sap develops under her protective shield (which, unlike the male, she never leaves) into an oval or rounded yellow mass: her legs, antennae, and even head become aborted though the segments of the abdomen are well defined in most species, and finally she becomes simply a sack of eggs. She deposits her eggs under the protection of the shield, in other cases the larvae develop within her shrunken dead skin.

The larvae swarm out and spread over plants when, owing to their immense numbers sucking up the sap with their sharp beaks, they soon injure the tissue and often kill the food plant. Thus from an economic point of view the scale insects are one of the most important groups of the insect-world that man has to deal with, and thousands of pounds are spent in spraying and fumigating cultivated trees to destroy these pests. Many species are cosmopolitan in their range and choice of food plants, having been introduced all over the world, but Australia has a great number of indigenous species, many remarkable for their curious habits, particularly those forming solid woody galls on the eucalypts.

The classification of the scale insects is based chiefly upon the structure of the adult female coccid, viz.:--Of the spinnerets, abdominal cleft, lobes, spines, and anal ring of the abdomen, and the structure and number of joints of the antennae. The shape and structure of the puparium or scale, or other secretions are used to separate them into the larger sub-divisions.

The greater number of our species were described by Maskell in the “Transactions of the New Zealand Institute between the years 1878–1898,” in which period he added over 100 new species to our list: Green (Pro. Linn. Soc. N.S.W. 1900) has described some others; and in the same Journal (1882–1898) I dealt with the gall-making coccids belonging to the sub-family BRACHYSCELINAE. In 1894 Maskell issued a “Synoptical List of the Coccidae reported from Australia and the Pacific Islands,” in which 180 species were credited to Australia. To this Maskell added later a number of new forms; and Fuller others from Western Australia (Trans. Ent. Soc. London 1899). In Mrs. Fernald’s “Catalogue of the Coccidae of the World” (Hatch Experiment Station Bulletin 88, 1903) over 328 species are listed, from this country, but there are a considerable number of doubtful species among them.

The COCCIDAE have been divided into a number of sub-families: I follow Green (Coccidae of Ceylon, 1896), though Mrs. Fernald in following Cockerell reverses the families and starts with the mealy bugs; I also retain most of the well-known generic names unless there is a very valid reason for discarding them, which does not appear to be the case in many of Cockerell’s amendments.

The Sub-family DIASPINAE are known as armoured scales and embrace most of the forms which cover themselves with stout horny shields (puparia). When adult the female is almost legless, with rudimentary antennae, and incapable of movement. The members of the Genus _Aspidiotus_ form round scales, and among them are some of our worst orchard pests. The introduced species _Aspidiotus auranti_, the Red scale of citrus trees, is now found on many garden shrubs. The puparium of the adult female is dull reddish yellow with the centre lighter coloured, and the twigs, leaves and fruit of neglected trees are often covered with these scales in all stages of growth. _A. perniciosus_, the notorious San José Scale, that attacks deciduous fruit-trees in the same manner, is a dull brown circular scale; its original home is somewhat doubtful, and though it was first recorded as a pest in California, is said to have come from China. The scales are much darker than those of the red scale, and infest the branches and twigs so thickly that they destroy the bark, and whenever they attach themselves to the fruit produce a red spot. _A. hederi_ (better known under the name of _A. nerii_), is a pure white scale with a yellow centre; it has a world-wide range, and its range extends far out into our western scrubs, sometimes covering the whole of a large tree. _A. rossi_ is a very distinct, round, black scale, partial to _Euonymus_ in the garden, and to grass trees in the bush. _A. ficus_ is often known as the “Round Scale” from its size and regular shape; it is deep chocolate brown in colour, common upon palms, and is sometimes found upon oranges coming from the Pacific Islands.

_Fiorinia acaciae_ covers the stems and twigs of _Acacia longifolia_ with its narrow white ribbed scale; it is much longer than broad, and is truncate at the extremities; this gives it a very distinctive character.

The Genus _Diaspis_ contains a number of delicate, more elongated scales, among which is the well known white rose scale _Diaspis rosae_, common in the garden. _Poliaspis exocarpi_ is another white scale infesting _Oxylobium_, _Dillwynia_, and other bush shrubs; the male scales are long, slender, and loosely attached to the smaller twigs.

The Genus _Chionaspis_, containing a number of cosmopolitan and indigenous species, has the base of the scale narrow, elongate, but broadly rounded at the extremity. _Chionaspis xerotides_ is white, common upon the blades of the sedge growing along the sea shore at Botany, N.S.W., and has a wide range. _C. eugeniae_ is a larger broader scale, variable in size and shape; it infests several native shrubs, and a very large form is found on the waratah.

_Mytilaspis_ is another world-wide genus, in which the scales are attenuated at the base and are oyster-like in shape; _Mytilaspis pomorum_ is the common “Mussel” or “Oyster” scale of the apple tree found all over the world. _M. spinifera_ is a handsome, broad, white scale common on the weeping myall (_Acacia pendula_), growing in the interior. _M. striata_ is a very slender form of scale that has had to adapt its shape to the slender foliage of the Casuarina which it infests. _M. acaciae_ is a grey species that clusters thickly together in masses like the apple scale, covering the stems of several different species of Acacias in the bush with its stout irregular scales.

Family =Coccidae=.

1. _Apiomorpha urnalis_ (Tepper).
2. _Frenchia semiocculta_ (Mask.).
4. _Frenchia casuarinae_ (Mask.).
3. Galls of Buprestid beetles (_Ethon corpulentum_,
Bohem.).]

In the Sub-family LECANIINAE the female coccids are active or stationary; naked or covered with some secretion; sometimes without legs; the abdomen marked with a median cleft and furnished with two dorsal lobes. Several species of the tropical Genus _Ceroplastes_ are found about Sydney, where they were introduced into the gardens at a very early date, and have since spread into the orchards and bush. The Indian wax-scale, _Ceroplastes ceriferus_, covers orchard trees, and bush and garden shrubs with its irregular rounded masses of greasy white matter that protect the liver-coloured coccids beneath. _C. rubens_ is a smaller and more regularly rounded dull red scale, the enveloping material forming a hard waxy shell.

The members of the Genus _Ctenochiton_ are chiefly confined to New Zealand, but two fine species have been described from Australia. _Ctenochiton eucalypti_ comes from the Newcastle district, N.S.W., where it infests the leaves of gum saplings. The scales of the sexes differ very much; those of the male are slender, white, and glassy, while those of the female are broad and dark coloured. _C. rhizophorae_ comes from Queensland, where it is found upon the mangrove. The beautiful, brittle, glass-like scales of _Inglisia foraminifer_ and _I. fossilis_, are often very plentiful in the interior on low scrub trees.

165. _Icerya purchasi_ (Maskell).

The Cottony-cushion or Fluted Scale of the orange tree.

166. _Ceroplastus ceriferus_ (Anderson).

The introduced Indian Wax Scale of citrus trees, etc.]

In the Genus _Ceronema_, the males form delicate angulated scales, but the females are clothed with a woolly secretion. _Ceronema banksiae_ is a somewhat rare scale found on the foliage of the banksia; it has the secretion upon the dorsal surface, formed into a distinct rib down the centre. _C. caudata_ is a large species with a white woolly covering, a large filament towards the apex forming a large loop rising above the back like a handle. It has a wide range from the South Coast of N.S.W. to North Queensland, and about Bulli, N.S.W., is found on gum trees.

The Genus _Lecanium_ (which has been cut up into a number of new genera) contains many distinct species peculiar to our fauna. _Lecanium tesselatum_, a flattened species with crenulated margins, and common on palms in the gardens, and _L. oleae_, known as “black bug” or “olive scale” by the orchardists, are both introduced species: _L. patersoni_ is a slender form found upon the foliage of _Patersonia glabrata_ growing about Sydney. _L. scrobiculata_ is a bright, shining, convex, dark brown scale infesting several species of acacias; and _L. mirificum_, one of the largest, is found in the interior upon _Acacia pendula_. The curious coccid, _Cryptes (Lecanium) baccatum_, covers the twigs of several acacias, among them the common black wattle in the vicinity of Sydney. At first dull white, they swell out into rounded bead-shaped, blue sacks, so close together that they encrust the whole of the infested twig; when adult they turn dull brown.

The Sub-family DACTYLOPINAE contains most of the well-known “mealy bugs”; they are soft bodied creatures in the earlier stages of their existence, and many species are able to move about until their latter days; instead of forming a separate scale like the first group, they cover themselves with white, woolly, mealy, cottony, or waxy secretions.

The members of the Genus _Asterolecanium_ are represented in Australia by the introduced “oak scale” _Asterolecanium quercicola_, a typical form which, half buried in the infested bark at the tips of the branches, is covered with a waxy, greenish yellow, rounded scale; when numerous it causes the tips of the branches to die back. _A. acaciae_, when numerous, aborts the bark and twigs of _Acacia longifolia_ and is covered with dull brown and white shields; and with _A. stypheliae_, with its raised, shining, oval, bright yellow tests, found on a number of different shrubs, are both native species with a very wide range over Australia.

The Genus _Rhizococcus_ is represented by 8 species, found chiefly upon the twigs of wattles (_Acacia_) and she-oaks (_Casuarina_); and the cosmopolitan Genus _Eriococcus_ by 17 species. Several species of _Eriococcus_ enclosed in their egg-shaped, white-felted sacks are very common in the forest, clustering over and often killing the young trees. _Eriococcus coriaceous_ varies from white to yellow in colour; the sacs are oval, with a distinct anal opening on the summit; they infest the foliage and twigs of many young Eucalypts. _E. paradoxus_ is a somewhat larger, sticky insect; they mass together in regular lumps on the twigs of the same trees: while _E. eucalypti_, as far as my experience goes, is never found on gum trees, as its name implies, but upon the prickly twigs of _Bursaria spinosa_, and its sacs are more depressed and have a browner tint.

The Eucalyptus scale. Natural size and enlarged.

(Original photo. T. Kirk).]

The typical _Dactylopius_ are free-moving insects, often crawling about until their final stage, when they become covered or surrounded with flocculent woolly matter. _Dactylopius albizziae_ is common on the black wattle, and is sometimes a pest in wattle plantations; it is a blackish-blue berry-shaped coccid surrounded with and lightly clothed on portions of the dorsal surface with white mealy and woolly filaments. _D. aurilanatus_ is chiefly confined to the branchlets of _Araucaria bidwilli_, or “Bunya Bunya.” It is very abundant at times on these trees in the Sydney gardens, and is easily recognised by the broad lines of sulphur-yellow meal or down across the dorsal surface. _D. lobulatus_ is an oval coccid, hiding under loose bark on the trunks of the blue gum, _Eucalyptus globulus_; it is so thickly clothed with white mealy secretion forming filaments round the edges that its form and colour are quite hidden.

In the Genus _Ripersia_ the species have a world-wide range; they are curious wrinkled naked coccids, but are sometimes more or less enveloped in a white covering; they lead an underground existence on the roots of grass and plants: a single species is recorded by Maskell from S. Australia on the roots of a _Leptospermum_. The curious _Antonina australis_ is an underground coccid which infests the roots of the Nut-grass, _Cyperus rotundus_, and was described by Green (Pro. Linn. Soc. N.S.W. 1904) from specimens obtained in the Hunter River district, N.S.W., where it was so plentiful that in the dry seasons it killed a great deal of this sedge. The adult female is a rounded black smooth shining creature about ⅛ of an inch in diameter, enveloped in a coat of white woolly secretion, from which it can be easily removed. The legs and antennae are aborted, but the segmental divisions of the abdomen remain, and the tip is produced into two irregular roughened tubercles, joined at the base with a tuft of stout bristle-like hairs.

Family COCCIDAE.

1. _Tachardia australis_ (Froggatt). On Melaleuca.
2. _Tachardia australis_ (Froggatt). Male and female
tests.
3. _Tachardia australis_ (Froggatt). Female coccid.
4. _Tachardia decorella_ (Maskell). On Eucalyptus.
5. _Tachardia decorella_ (Maskell). Female in test.
6. _Tachardia decorella_ (Maskell). Female exposed.
7. _Tachardia decorella_ (Maskell). Larva.]

The Sub-family TACHARDIINAE contains a number of remarkable species, some of considerable commercial value on account of the resinous secretion they encrust themselves with; this secretion is known as lac, and is used for making varnish. The typical female is an irregular wrinkled fleshy mass with a pair of tubular appendages on the back. These appendages were supposed at one time to be used for producing the lac, but Green considers them to be breathing structures. Five species are described from Australia, of which _Tachardia australis_ is so thickly encrusted with reddish brown lac, that it might be of some commercial value in the future; it is very plentiful upon Melaleuca bushes near Maryborough, Queensland, but was described by me from specimens obtained on a small shrub, _Beyeria viscosa_, at Gunnedah, N.S.W. _T. decorella_ is enclosed in a very dainty, flattened, ribbed, cushion-like mass of dull slate-coloured lac; it is found on a number of different trees, among them the water gums (_Eugenia smithii_); and I have also found it on the desert cypress (_Callitris_) in the interior.

The Nut-grass Coccid.

1. Nut-grass showing coccid upon the roots.
2. Adult female coccid removed from enveloping cover
(enlarged).]

The Sub-family IDIOCOCCIINAE comprises a number of very curious coccids, some of which are naked; some form waxy tests; while others are enveloped in woody galls. Maskell, who created this division, says they are separated from the MONOPHLEBIINAE by the absence of anal tubercles and the antennae, and from the BRACHYSCELIINAE by the absence of anal appendages. The members of the Genus _Sphaerococcus_ number 21 described species, all but two of which are peculiar to Australia; some form galls, others waxy tests. _Sphaerococcus pirogallus_ cover the whole of the tips of the bushes of _Leptospermum flavescens_ with its curious little pear-shaped galls. At first pink or red, these galls are dull brown when full grown, and have an aperture on the side of the stalk, and the coccid within is attached to a saucer-like rim on the roof of the apex. This is one of the commonest galls about Sydney; acres of these low bushes often have the whole of their foliage covered with masses of these small galls. _S. melaleucae_ does not form a gall, but surrounds itself with a dark waxy secretion like the lac insect; both scales and twigs are often blackened with smut or fumagine. _L. leptospermi_ forms a swelling in the twig which looks as if the tissue had risen over it like a blister and then split down the middle, exposing the dorsal surface. _S. froggatti_ is very common on the tips of Melaleuca bushes growing about Sydney; the dull red coccid is clothed with white secretion resting in an excrescence fringed with slender, reddish brown finger-like processes curling over in an irregular protective gall. _S. socialis_ produces a very curious greyish globular gall with no opening on the outside, and measures up to ½ an inch in diameter. Maskell says: “The outer surface is formed of very closely imbracted scales, which are apparently aborted and coalesced leaves of the tree”; the interior is of a loose structure containing several female coccids, and a few males. It was collected by Lea near Geraldton, W. Australia.

The Genus _Cylindrococcus_ contains 3 species which form curious cone-like galls upon the twigs of the She-oak, _Casuarina_. _Cylindrococcus spiniferus_ varies much in size and shape. They are often very numerous, covering the whole of the bush with their curious, rough, bracteate galls, which are rounded at the base and taper to the extremity. The female, a cylindrical, dull red creature, is enclosed in an elongate, thin tube, which occupies the centre of the gall; this tube is attached at the base of the gall and is surrounded with the bracts. Some of the typical forms might be easily mistaken for seed cones. _C. amplior_, which is a more solitary species, forms a solid seed-shaped gall with the base set in a bract like the calyx of a flower, and the whole might be likened to an unopened bud. It is found in South Australia and the north-western parts of Victoria.

Family COCCIDAE.

1. _Apiomorpha duplex_ (Schr.). ♀ Gall.
2. _Sphaerococcus leptospermi_ (Mask.). ♀ Galls.
3. _Cylindrococcus spiniferus_ (Mask.). ♀ Galls.]

The Sub-family BRACHYSCELIINAE contains some of the most remarkable insects in our fauna. They were first noticed by Schrader (Trans. Ent. Soc. N.S.W. 1862), who described and figured a number of our commonest species and their galls; to these I have added a number of new species (Pro. Linn. Soc. N.S.W. 1892–1898). They are all gall makers; the beautiful little larva born in the gall is usually yellow, oval, flattened, and fringed round the margin with short glassy filaments. In most species the full-grown female has antennae and legs aborted, and becomes simply a sac of eggs and liquid matter enclosed in a leathery skin, and is furnished with horny tail appendages.

The Genus _Frenchia_ was formed by Maskell for a species, _Frenchia casuarinae_, which forms a gall like a stout blunt thorn; it is about the thickness of a slate pencil and has a small opening at the apex. These twig-like galls spring directly from the branch of the infested _Casuarina_, while the aborted tissue at the base swells out like a blister. The slender, attenuated, red female coccid rests head downward with the tail reaching up to the apical orifice of the gall. A second species, _F. semiocculta_, forms a raised swelling on the twigs of _Casuarina_, with a cleft in the centre, thus forming two lobes. The first is common in Tasmania, Victoria, and N.S. Wales; the latter was collected at Manly, near Sydney.

Schrader called the next Genus _Brachyscelis_, but Rubasmann finding the name preoccupied changed it to _Apiomorpha_; over 30 species are given in Mrs. Fernald’s Catalogue, but there are several species described both by Rubasmann and Tepper that were described from variable or aborted galls that may prove to be synonyms. The female is remarkable for forming a stout woody gall, sometimes sessile, sometimes springing from a stalk; it encloses an oval cell with a circular or transverse aperture at the apex of the gall, through which the male impregnates her by means of his long slender abdomen. The young larvae are hatched within its shelter, and crawl out to reach their food plant. The female is a top-shaped (turbinate) creature encased in a leathery skin, more or less clothed with fine hairs, enveloped in a mealy secretion, with rows of fine spines on the dorsal surface of the abdominal segments, and the body terminating in two horny tails (anal appendages). The head is merged into the thoracic portion, and has the ventral surface wrinkled and bearing a rudimentary mouth; the antennae and legs are aborted. The only distinct specific characters are the dorsal spines and the form of the anal appendages. The males are delicate two-winged insects, with long antennae, slender legs, and the body very long and attenuated, ornamented with two fine filaments. They either form single short tubular galls on the leaves, or form masses of the same tubular galls; or they are placed in rows enfolded in a hood growing from the side of the female gall like a small cockscomb. All the members of this genus are confined to the eucalypts.

_Apiomorpha duplex_ is the largest insect-gall in the world. Springing directly from the twig, it swells out into a stout four-sided gall, 1½ inches in diameter, 3 inches in length; beyond this the apex of the gall is produced into two stout flattened appendages extending another 9 inches. The enclosed female coccid measures up to 1½ inches. _A. munita_ forms an angulated gall rounded at the base, with each angle on the apex furnished with a slender curled horn, but it is very variable both in form and size. _A. pileata_ is an egg-shaped gall, with the apex truncate and forming two lips, the apical orifice forming a keyhole-like slit between them. We have two varieties of this gall, which in their immature state have a membranous tailed cap covering the apex which dries and falls off as the gall matures, leaving the apical orifice exposed. _A. pomiformis_ is shaped like and about the size and shape of a small apple, with the apical orifice situated in a depression in the centre. It is a North Australian form, and is also found on stunted gums in the interior. Specimens of a large gall received from Tennant’s Creek, Central Australia, with the enclosed coccid, show that the structure of the coccid is very different from the _Apiomorpha_ the anal extremity being thimble-shaped, fitting against the apical orifice, so it will require to be placed in a new genus. _A. dipsaciformis_ is an oval gall covered with curled filaments like a “teasel.” In the group in which the male galls are formed on the side of the oval female gall, _A. pharatrata_ is a typical form; the female gall is oval, overshadowed with the mushroom-shaped mass of coalesced tubular galls growing out near the apex.

The female coccids of the Genus _Opisthoscelis_, as they change from the larval stage, lose almost every vestige of the first two pairs of legs, while the hind pair are produced into long attenuated appendages, which in some species (when enclosed in the gall) curve round over the back like hairs; the whole insect is rounded or top-shaped, with a peg-shaped anal appendage. Thirteen species are described, all of which produce galls upon different species of eucalypts. _Opisthoscelis subrotunda_ is our commonest species; the solid fleshy galls, about the size of a pea, often cover and abort much of the foliage of the infested tree. The short rounded coccid fits tightly to the cavity, and the opening, closed by the tip of the anal peg, is on the under side of the leaf. Schrader has described the male galls of this species, which are probably very rare, and I have never been able to discover them.

The short, slender, reddish, tubular galls of _O. spinosa_ are as plentiful as the curious thorn-shaped female galls, which latter have the opening at the tip, and are common on the foliage of the large-leaved ironbark, _Eucalyptus siderophloia_, growing around Sydney. The female coccid, in this and several of the other gall-making coccids with the spine or thorn-shaped structure, is firmly attached to the sides and base of the cavity, and is difficult to remove without damage. The galls of the Genus _Ascelis_ are often dissimilar in form; that of _Ascelis praemollis_ is rounded, with the opening on the under side of the leaf, and except for the shape of the scar and larger size might without close examination be taken for that of _Opisthoscelis subrotunda_; but the enclosed insect is a very different looking creature; it is simply an irregular jelly-like mass, with a short peg-like structure rising from what looks to be the back, but is the tip of the abdomen; this structure is produced into three finger-like projections, which, holding a lump of gummy substance, plug up the basal opening in the gall. _A. schraderi_, which forms a circular, flattened, blister-like gall in the tissue of the leaves of _Eucalyptus corymbosa_, is more flattened, with the anal tail truncate at the apex, without the curious finger-like appendages, and the anal aperture as fine as a pin prick is on the upper surface of the leaf.

I have gone somewhat extensively into the description of these gall-making coccids, owing to the fact that they form such remarkable structures, and differ from all other solid galls in the fact that they are formed by the larvae and are not the result of eggs deposited beneath the plant tissue. Specialists in the study of vegetable growths may find some key to the mystery of gall development in this fact.

The MONOPHLEBIINAE comprises a number of large “mealy bugs,” so called because they form no protective scale, but are simply clothed with a mealy secretion, fine filaments or masses of felted wool. The females are often of considerable size, and during the greater part of their existence are capable of crawling about, but when adult and about to lay their eggs they often become fixed to the food plant. The males are of the usual two-winged type with long antennae and the tip of the abdomen fringed with fine filaments. This division has been cut up into a number of sub-families by Cockerell, and these divisions are given in Mrs. Fernald’s Catalogue, but here I propose to place them together under the one sub-family.

The Saltbush Mealy Bug of the interior.

_a_, Male; _b_, Showing the male enclosed in pupal
test; _c_, Larva; _d_, Ventral view of adult female.

(“Agricultural Gazette,” N.S.W.)]

_Monophlebus crawfordi_ is one of our largest species; the female measures about 1 inch in length and is broad in proportion; she is dull orange yellow marked with parallel bars of purple, and fringed round the edges with fine hairs; and is of a general flattened, broad, oval form, with the dorsal surface distinctly segmented. She is generally found clinging to the stem of a smooth-barked eucalyptus tree, sometimes half hidden under a bit of loose bark and surrounded with white mealy secretion. When egg-laying she sometimes produces a great quantity of fine curled cottony filaments forming a mass much larger than the original size of her body, under which the eggs are deposited.

The Genus _Callipappus_ contains 6 Australian species; the females are flattened, oval, irregularly segmented coccids of a dull brown to purplish red tint, which are usually found crawling about on tree trunks. _Callipappus australe_ was described by Maskell (Pro. Linn. Soc. N.S.W. 1890) under the generic name of _Coelostoma_, a group confined to N. Zealand. The male is a beautiful two-winged insect of a general deep red colour, the wings rose-pink, and the tip of the abdomen clothed with a large bunch of silky white filaments like a tuft of spun glass; from this latter character it has received the fanciful but rather appropriate name of the “Bird of Paradise Fly.” The female is of an oval, flattened form about an inch in length; the body is irregularly segmented and lightly clothed with flakes of a mealy secretion. When depositing her eggs, generally on the trunk of a tree, she becomes attached to the bark with a patch of silk on the ventral surface of the body; the body swells irregularly, the extremities of the abdomen shrink and turn upwards, the whole body later becoming simply a dry shell. Guérin described a species, _C. westwoodi_, from West Australia; and Fuller a few years ago re-described this and named two new species.