II.—The Genera of Recent and Tertiary Rhynchonellids

Publisher Website
Google Scholar
Abstract
Owing to the marked persistence of general external form and internal characters in the Rhynchonellidæ, it is necessary in this family to seize on slighter differences for the foundation of genera than is elsewhere necessary or advisable. The object of this paper is to point out the characters that have been used and others which may advantageously be introduced in the discrimination of the genera of Recent and Tertiary representatives of the group. These are not at present distributed by authors amongst the genera Rhynchonella, Fischer; Acanthothyris, d'Orbigny ; Hemithyris, d'Orbigny ; Cryptopora, Jeffreys (syn. Atretia, Neatretia); Frieleia, Dall; and Basiola, Dall.

This publication has 2 references indexed in Scilit: