NEVADA FOSSIL SPONGE FAUNA — BASSLER 93 



1927. Bibliographic references to this paper are oniilled in the 

 present one since all descriptions previous to Patellufongia are 

 j>rinted on page 392, while that genus and Hesperocoelm are described 

 on page 393, and the Anthaspidellidae on page 394. Again, the 

 horizon and locality are not mentioned each time because for all 

 the species it is, as stated before, the Upper Pogonip (Chazyan) lime- 

 stone, one-half mile south of Ikes Canyon, 4 miles west of Dianas 

 Punch Bowl on the eastern front of the Toquima Range, Roberts 

 Mountain quadrangle, Nev. The same assemblage of species occurs 

 in Ikes Canyon itself, as mentioned before. 



All the illustrations of this paper are unretouched photographs, 

 except that the pore structure has been emphasized enough to make 

 it visible. The photography of the thin sections proved difficult, 

 since on enlargement the definite structure of the spicules loses much 

 of its clearness. 



Subclass SiLiciSPONGiAE : Order Tetractinellida 

 Family ARCHAEOSCYPHIDAE Rauff 



Archaeoscyphidae Rauff, Paleontographica, vol. 40, p. 2.38, 1894. 



Sponge attached, simple or branching, ranging from narrow 

 cylindrical to saucer or funnel shaped, turbinate and frondescent 

 forms M'ith simple or branched cloaca usually of considerable diam- 

 eter ; oscula represented by numerous often closely spaced, small pores 

 penetrating the spicular tissue of the wall as definite canals and 

 opening on the outer surface at regular intervals. 



With the recognition of five genera in the Nevada Pogonip fauna, 

 this family, formerly based upon a single species of the genus 

 ArcKaeoHcypMa^ assumes some importance in the early Ordovician 

 rocks. 



Genus ARCHAEOSCYPHIA Hinde, 1S89 



Archaeocyathus (part) Billings. Paleozoic fossils, Geol. Svirv. Canada, vol. 1, 



p. 354, 1865. 

 Archaeoscyphia Hinde, Quart. Journ. Geol. Soc. London, vol. 45, p. 142, 1889.— 



Rauff. Palaeontographica, vol. 40, p. 2.38, 1894. 



Sponge simple, attached, short but rapidly expanding funnel-shaped, 

 6 cm. or more high and about 4 cm. wide, with a broad cloaca 3 cm. 

 in maximum diameter and the outer surface bearing strongly marked, 

 angidar, parallel, transverse ridges. Wall 5 mm. thick, lined on 

 both the inside and outside by longitudinal rows of closelj'- spaced 

 pores traversing the spicular skeleton, which consists of minute sili- 

 ceous spicules of the tetractinellid type with the rays slightly branched 

 at their extremities and interlocking without forming prominent 

 nodes. 



