OK THE GEXUS REMONDIA, GABB, A GROUP OF 

 CRETACEOUS BIVALVE MOLLUSKS. 



By Timothy W. Stanton, 



Custodian of Mesozoic Invertebrates. 



In 18G9 W. M. Gabb^ described a small collection of Cretaceous 

 fossils obtained by Auguste Remond de Corbineau near Arivecbi, in 

 the State of Sonora, Mexico. The horizon is now known to be about 

 the sau!e as that of the Comanche Peak limestone, which is near the 

 middle of the Texan Comanche series. Among these fossils were sev- 

 eral specimeus of a peculiar shell for which Gabb jjroposed the generic 

 name Bemondinj with the followiug description: 



" Shell compressed, elongate subquadrate, closed at the extremities 

 (or perha]js slightly gaping posteriorly). Ligament very short, exter- 

 nal. Hiuge compos 3d of three radiating cardinal teeth in each valve, 

 and a long ijosterior tooth in the left with a corresponding tooth in 

 the right. The middle cardinal tooth of the left valve is transversely 

 striated as in Trif/onia, and is slightly grooved on its face; the anterior 

 is linear and smooth, and the posterior is also smooth, at least on its 

 posterior face. The posterior lateral and its corresponding cavity are 

 irregularly rugose. In the right valve the anterior tooth is as large as 

 the middle; the posterior is linear; further details uuknown. 



"This genus is evidently closely allied to TrUjonla, its quatlrate form 

 not being unlike many of the species of that genus, and the trans- 

 versely striate teeth showing a marked resemblance.-' 



Type. — Remondia fu)-cata, Gabb. 



The genus has been recognized in the manuals of conchology and 

 paleontology and placed in the Tfigoniidte by Tryon, Zittel, and 

 Fischer, though the latter remarks that it would i^erhaps be better 

 placed near Astarte. Stoliczka referred to it Astarte bronnii, Krauss, 

 from the Lower Cretaceous of South Africa, and recently Cragin^ has 

 described a species, Remondia ferrissi, from the Lower Cretaceous of 

 southern Kansas. 



'Paleontology of California, II, pp. 257-276. 



-Amer. Geol., XIY, July, 1894, p. 5, pi. i, fig. 1; Bull. Washburn College Lab. Xat. 

 Hist., II, No. 10, p. 68. 



Proceedings U. S. National Museum, Vol. XIX— No. 1109. 



299 



