Chapter D: ANGUINUM. D. spira inæquali angulata aculeata, sulco

longitudinali perforata.

Rumph. 125. t. 41. f. H. Solen anguinus.

Lang. Test. 6. Tubulus vermicularis crista dentata.

Testa albida, teretiuscula, angulis 9 obsoletis. Anfractus inæquales, nunc confertiores, nunc remotiores. Sulcus longitudinalis in superiore latere perforatus serie punctorum. Spinæ breves, fornicatæ ad angulos in latere inferiore.

Condensation, that peculiar faculty of the mental organization of Linnæus, induced him to suppress this description, and attach the species, as a variety, to the form he had simultaneously characterized as _D._ spira elongata, teretiusculum, inerme, fissura longitudinali. Gualt. test. 10. f. z.

To this latter the published details belong, except the expression "passim concatenata et quasi poris pertusa" (which was a subsequent and fallacious addition), and the account of the variety.

S. PENIS. _D._ teres, extremitate radiata disco cylindris poroso.

"Bonan. i. f. 38.", indicated in the tenth edition of the 'Systema', was among the synonyms. The "Stigma, &c." was an addition; so too were "lævis," "tubulosis", and "æqualibus". The term "hemisphærico" has replaced the earlier "convexo."

In addition to the published species, the _S. Spirorbis_ of the 'Systema' appears to have been indicated as