452 PROCEEDINGS OF THE ACADEMY OF [1890- 



Gryphaea mucronata. 



I see no reason to separate this species from Gryphcea navia Con- 

 rad ( G. Pifcherl f Morton), despite the points of difference indica- 

 ted by Gabb. Dr. White, in his review of the " Fossil Ostreidse of 

 North America," has correctly referred it to that species.' 



Cardita alticosta. 



This species is unrecognizably figured. The radiating ribs are 

 in nearly all cases prominently echinated — instead of being smooth 

 — and they are placed much closer to one another than appears in 

 the drawing. As the specific name alticosta is preoccupied by a 

 well-known fossil from the Tertiary deposits of the United States 

 (^Cardita alticosta Conrad -f C. Blandiiigi), I would propose for the 

 Mexican species the name Cardita Arivechensis. 



Trigonia Mooreana. 



Gabb is right in separating Roemer's Trigonia crenidata of Texas 

 from the true Trigonia crenulata of Europe. The closely placed 

 ribs of the latter, and its deep lunular groove, serve readily to dis- 

 tinguish it from Trigonia Mooreana. 



Bemondia furcata. 



This peculiar trigonioid species, for which Gabb created the new 

 genus Remondia, is seemingly closely related to Astarte Bronnii, of 

 Krauss, from the Cretaceous deposits of South Africa.^ I know of 



1 4th Annual Report Director U. S. Geol. Survey, 1884, p. 302. As regards 

 the species or varieties of grypheate oysters occurring in the Cretaceous deposits 

 of the southern United States, and known as Gryphea Pitcheri, G. dilaiata, G. na- 

 via, G. Tucumcarrii anA G. Washitaensis, I beheve they are all referable to a sin- 

 gle, or at most, two species — Gryphea Pitcheri (Morton) and G. navia (Conrad). 

 Whether or not these two should be considered distinct, will depend upon the 

 view of species which each paleontologist holds. They are certainly very closely 

 inter-related, and I believe that Dr. White is right in recognizing only G. Pitcheri 

 and G. Pitcheri var. navia [Loc. cit. pp. 302-3. Gryphea Pitcheri was first de- 

 scribed from the Cretaceous deposits of Arkansas, and not from New Jersey, as 

 is sometimes assumed). Roemer's figures (Plate IX, figs, la, b, c — Krei- 

 dehildungen von Texas, 1852) represent the variety navia, as do likewise figs. 5 

 and 6 of Marcou's Plate IV (Geology of North America, 1858). Gryphea Wash- 

 itaenns of Hill (Annotated Check List Cretac. Invert. Fossils Texas, Bulletin 4, 

 Geol. Survey of Texas, p. 4, 1889), specimens of which Professor Hill has kindly 

 sent to me, is true G. Pitcheri, corresponding almost absolutely with the type 

 specimen of that species (Morton's) which is contained in the collections of the 

 Academy of Natural Sciences. 



* Nova Acta Acad. Cresar. Leop. Carol., XXII, p. 449, pi. 48, figs. 1, a, b 

 c, d, e. 



