Chapter IX: Section X: Microsauria, Dawson

Genera: _Dendrerpeton_, Owen; _Hylonomus_, Dawson; _Hylerpeton_, Owen.

The schemes of classification used for the next 10 years did not depart in any appreciable degree from those already given.

In 1875 Cope, in his Check-list of North American Batrachia and Reptilia (120), with a systematic list of the higher groups, published the following classification as being "adopted provisionally by the Smithsonian Institution":

Class Batrachia.
Order Anura. (Anura, Duméril; Salientia, Merrem, Gray.)
Raniformia. (Raniformia, Cope, Nat. Hist. Rev., V, 114, 1865.)
Families: _Ranidæ_, _Colostheidæ_.
Firmisternia. (Bufonoid Raniformia, Cope, Jour. Acad. Nat. Sci.,
Philadelphia, n.s., VI, 190, 1867.)
Families: _Dendrobatidæ_, _Phryniscidæ_, _Engystomidæ_,
_Breviceptidæ_.
Gastrechmia. (Gastrechmia, Cope, Jour. Acad. Nat. Sci.,
Philadelphia, n.s., VI, 198, 1867.)
Family: Hemisidæ.
Bufoniformia. (Bufoniformia, Duméril et Bibron, _partim_; Cope,
_partim_.)
Families: _Rhinophrynidæ_, _Bufonidæ_, _Batrachophrynidæ_.
Aglossa.
Family: _Pipidæ._
Odontaglossa.
Family: _Dactylethridæ._
Arcifera. (Arcifera, Cope, N. H. Rev., V, 104, 1865.)
Families: _Cystignathidæ_, _Hemiphractidæ_, _Hylidæ_,
_Scaphiopidæ_, _Pelodytidæ_, _Asterophrydidæ_, _Discoglossidæ_.
Order Stegocephali. (Stegocephali Cope, Proc. Acad. Nat. Sci.,
Philadelphia, 1868, 209.)
Labyrinthodontia.
Families: _Baphetidæ_ Cope, _Anthracosauridæ_ Cope.
Ganocephala.
Family: _Colosteidæ_ Cope.
Microsauria.
Families: _Phlegethontiidæ_ Cope, _Molgophidæ_ Cope, _Ptyoniidæ_
Cope, _Tuditanidæ_ Cope,
_Peliontidæ_ Cope.
Order Gymnophiona. (Gymnophiona Müller.)
Family: _Cœciliidæ_ Gray, 1850.
Order Urodela.
Families: _Pleurodelidæ_ Gray, 1858; _Salamandridæ_: Gray, 1858;
_Hynobiidæ_ Cope, 1866; _Desmognathidæ_ Cope, 1866; Thoriidæ
Cope, 1869; _Plethodontidæ_ Cope, 1866; _Amblystomidæ_ Cope,
1866; _Menopomidæ_ (_Protonopsidæ_ Gray, 1850), _Amphiumidæ_
Cope, 1866; _Cocytinidæ_ Cope.
Order Proteida.
Family: _Proteidæ_ Gray, 1850.
Order Trachystomata.
Family: _Sirenidæ_ Gray, 1850.

In 1885 Cope proposed 2 new orders, which he arranges with the other orders already known, as follows:

{ Order I. Rachitomi. Order V. Urodela.
Batrachia. { Order II. Embolomeri. Order VI. Trachystomata.
{ Order III. Stegocephali. Order VII. Anura.
{ Order IV. Proteida.

The new order Rachitomi was to include forms like Eryops and the new order Embolomeri was to include forms like Cricotus; the other orders were as they had been given before.

Zittel in 1888 proposed (642) the next classification of any note in his "Handbuch der Paleontologie," where it stands as follows:

Classe Amphibia.
Ordnung 1. Stegocephali.
Unterordnung 1. Lepospondyli.
Familie 1. _Branchiosauridæ_ Fritsch.
" 2. _Microsauria_ Dawson.
" 3. _Aistopoda_ Miall.
Unterordnung 2. Temnospondyli.
Genera: _Archegosaurus_, _Eryops_, etc.
Unterordnung 3. Stereospondyli.
Familie 1. _Gastrolepidoti_.
" 2. _Labyrinthodonta_.
Ordnung 2. Cœciliæ.
Ordnung 3. Urodela.
Unterordnung 1. Ichthyoidea.
Familie 1. _Phanerobranchia_.
" 2. _Cryptobranchia_.
Unterordnung 2. Salamandrina.
Ordnung 4. Anura.
Unterordnung 1. Phaneroglossa.
Familie 1. _Ranidæ_.
" 2. _Bufonidæ_.
" 3. _Cystignathidæ_ Cope.
" 4. _Pelobatidæ_ Boul.
" 5. _Discoglossidæ_ Cope.
" 6. _Palæobatrachidæ_ Cope.

Lydekker (393) in the next year proposed a system of classification which did not depart widely from that proposed (450) by the committee of the British Association for 1874. Lydekker's classification is as follows:

Class Amphibia.
Order I. Labyrinthodontia.
Suborder 1. Branchiosauria.
Family _Protritonidæ_.
" _Apateonidæ_.
Suborder 2. Aistopoda.
Family _Dolichosomatidæ_.
Suborder 3. Microsauria.
Family _Urocordylidæ_.
" _Limnerpetidæ_.
" _Hyloplesionidæ_.
" _Microbrachidæ_.
Suborder 4. Labyrinthodontia vera.
Family _Archegosauridæ_.
" _Diplospondylidæ_.
" _Nyraniidæ_.
" _Dendrerpetidæ_.
" _Anthracosauridæ_.
" _Mastodonsauridæ_.
Uncertain family, _Eosaurus_.
Order II. Apoda.
Order III. Caudata.
Family _Hylæobatrachidæ_.
" _Sirenidæ_.
" _Proteidæ_.
" _Amphiumidæ_.
" _Salamandridæ_.
Order IV. Ecaudata.
Family _Discoglossidæ_.
" _Pelobatidæ_.
" _Palæobatrachidæ_.
" _Cystignathidæ_.
" _Ranidæ_.

In 1890 Döederlein proposed a scheme of classification which is notable on account of the peculiar relations which it expresses between the groups relations which, in reality, do not exist. His classification is as follows:

Class Amphibia.
Ordnung I. Stegocephali.
A. Microsauria.
Unterordnung 1. Branchiosauri.
Genera: _Branchiosaurus_, _Dawsonia_, _Melanerpeton_,
_Pelosaurus_.
Unterordnung 2. Sauromorphi.
Familie 1. _Hylonomidæ_.
" 2. _Nectridæ_.
" 3. _Aistopodidæ_.

B. Ganocephala.
Unterordnung 1. Rhachitomi.
" 2. Embolomeri.
" 3. Labyrinthodontia.
Ordnung II. Urodela.
Ordnung III. Gymnophiona.
Ordnung IV. Anura.

In 1890 Lydekker used the same classification, with minor changes, which he had used in his Paleontology. Credner, who wrote at about the same time (193), followed Zittel's classification. Zittel in 1895 merely repeated his former classification. In 1898 appeared Smith Woodward's Paleontology, where the following scheme is adopted:

Class Batrachia.
Order I. Stegocephalia. Order II. Gymnophiona.
Suborder 1. Branchiosauria. Order III. Caudata.
" 2. Aistopoda. Order IV. Ecaudata.
" 3. Microsauria.
" 4. Labyrinthodontia.

Hay's Catalogue of Fossil Vertebrata of North America contains the next scheme for the classification of the Amphibia which pays especial attention to the extinct forms. His classification is as follows:

Class Batrachia Macartney, 1802.
Order Stegocephali Cope, 1868.
Suborder Microsauria Dawson, 1863.
Family _Protritonidæ_ Lydekker, 1889.
Genera: _Amphibamus_ Cope, _Pelion_ Wym.
Family _Molgophidæ_ Cope, 1875.
Genera: _Phlegethontia_ Cope, _Molgophis_ Cope.
Family _Hylonomidæ_ Fritsch, 1883.
Genera: _Hylonomus_ Dawson, _Smilerpeton_ Dawson, _Hylerpeton_
Owen, _Fritschia_ Dawson; _Brachydectes_ Cope.
Family _Ptyoniidæ_ Cope, 1875.
Genera: _Keraterpeton_ Huxley, _Œstocephalus_ Cope, _Ptyonius_
Cope, _Ctenerpeton_ Cope.
Family _Tuditanidæ_ Cope, 1875.
Genera: _Tuditanus_ Cope, _Cocytinus_ Cope.
Family _Diplocaulidæ_ Cope, 1881.
Genus: _Diplocaulus_ Cope.
Lepospondylous Genera of uncertain position: _Amblyodon_
Dawson, _Hyphasma_ Cope, _Eurythorax_ Cope, _Thyrsidium_
Cope, _Pleuroptyx_ Cope, _Cercariomorphus_ Cope.
Suborder Apœcospondyli Hay, 1902.
Family _Dendrerpetontidæ_ Fritsch, 1889.
Genera: _Dendrerpeton_ Owen, _Baphetes_ Owen, _Platystegos_
Dawson.
Family _Sauropleuridæ_ Hay, 1902.
Genera: _Sauropleura_ Cope, _Leptophractus_ Cope.
Family _Archegosauridæ_.
Genera: _Trimerorhachis_ Cope, _Dissorophus_ Cope.
Family _Cricotidæ_ Cope, 1884.
Genera: _Cricotus_ Cope.
Family _Anthracosauridæ_.
Genus: _Eosaurus_ Marsh.
Family _Eryopidæ_ Cope, 1882.
Genera: _Eryops_ Cope, _Ichthycanthus_ Cope, _Zatrachys_ Cope,
_Anisodexis_ Cope, _Acheloma_ Cope.
Family _Mastodonsauridæ_ Huxley, 1863.
Genera: _Mastodonsaurus_ Jaeger, _Eupelor_ Cope, _Pariostegus_
Cope, _Dictyocephalus_ Leidy.
Order Urodela.
Genera: _Scapherpeton_ Cope, _Hemitrypus_ Cope.
Order Salientia Laurenti, 1768.
Family _Ranidæ_.
Genera: _Rana_ Linné, _Eobatrachus_ Marsh.

This classification given by Hay is only for the forms which occur in North America.