CEASSATELLITES. 363 



Family CEASSATELLITIDiE. 



Genus CEASSATELLITES, Kriiger. 



[Geschichte der IJrwelt, Tlieil ii. 1823, p. 466.] 



CrassateUa, audorum {no7i Lamarck, Mem. Soo. Hist. JS^at. Paris, 

 1799, pp. 85, 86). 



American authors ' for some time past have recognized that the 

 name CrassateUites, Kriiger, must be applied to moUusca commonly 

 known as CrassateUa. In Lamarck's work above cited the type 

 of his CrassateUa is given as Madra cygnea, Chemnitz (^ M. cygmis, 

 Gmelin), which may, without hesitation, be referred to the Mactrida3, 

 and CrassateUa must therefore be employed for certain members of 

 that family, or fall in synonymy. Kriiger's type, mentioned below, 

 comes from the Bordeaux area. 



Type. — CrassateUa sinuata, Lamarck. 



CrassateUites dennanti, Tate (sp.). 



1886. CrassateUa dennanti, Tate, Trans. Eoy. Soc. South Anst. vol. ™i. 



p. 146, pi. xi. fig. 2. 

 1893. CrassateUa dennanti, Tate and Dennant, id. vol. xvii. pt. 1, p. 224. 



Shell large, truncated posteriorly, ventral margin slightly crenu- 

 lated in the adult ; surface ornament consisting of concentric ridges, 

 the last two or three developed posteriorly commonly run off the 

 ventral margin as the anterior of the shell is reached ; posterior 

 ridge rounded, well developed. 



Dimensions. — Height 37 ram. ; length 54 mm. 



Form, and Loc. — Eocene : Muddy Creek, Victoria. 



L. 4837. Eight valve of the adult ; and examples of the brephic 

 and ncaiiic stages of growth. Presented by John Dennant, Esq. 



L. 6588. Examples of both valves. Purchased. 



L. 9852. Both valves of the adult. Purchased. 



> Cf. R. B. Newton, Journal of Conchology, vol. \m. 1896, p. 150. 



