6o Cincinnati Society of Natural History. 



"Subglobose, more or less depressed, with a shallow cavity 

 on one side. Surface rough and generally covered with pit- 

 like markings ; sometimes quite distinctly lobed ; examples 

 examined not very satisfactory," (The Paleontologist, No. i. 

 July 2, i<S7.S. p. I.) 



The above is the original description. Some specimens ex- 

 amined show a series of hexagonal plates with depressed lines 

 running from the center to the six corners. Owing to the 

 crushed conditions of the specimens, these plates sometimes 

 appear round or oval. Internal structure unknown. 



Locality. - Cincinnati, Ohio. 



Remarks. — This species was originally described as Asty- 

 losponi>;ia tiimidus. It is referred here to J^asccolus with a 

 query, since it seems more nearly related to that genus than 

 Astylospongia. The form needs fuller investigation. 



Genus 8. — Recp:ptaculitks, DeFrance, 1827. 



" Cup or platter-shaped bodies of considerable size, with 

 walls of definitely arranged spicules. The outer surface is 

 formed by the rhomboidal head plates of the spicules; be- 

 neath these are the horizontal rays and robust sub-cylindrical 

 vertical rays, which are connected with an inner layer or per- 

 forated plate. Communication with the exterior was carried 

 on between the margins of the summit plates of the spicules 

 on the outer surface, and through the cylindrical canals of the 

 inner surface layer, or, according to Gihnbel, through inter- 

 marginal canals." (G. J. Hinde, on Receptacultida\ Quart. 

 Jour. (jCoI. Soc, Lond., vol. 40, 1884, p. 826.) 



Rniiarks. — The genus was originally described by DeFrance 

 in 1827 (I)ictionnaire des vSciences Xaturelles, Tome 45, p. 5). 

 Its position in classification has been a matter of dispute, and 

 it is still very doubtful. Hinde (Ibid) concluded it belonged 

 to the sponges. Billings (Palaozic Fossils, vol. i, 1865, p. 386) 

 thought its affinities were with Foraminifera ; while other 

 writers have considered it a cystidean, a coral or a tunicate 

 mollusk. Nicholson and Lydekker (Manual of Palaeontology, 

 vol. II, 1889,) do not consider its position as at all definitely 

 settled. For a full discu.ssion of the famil)- and its affinities, 

 con.sult Hinde's paper as above, and for details of the structure 

 of the genus, the remarks of Billings, al.so referred to above. 



