58 



COELENTERATA— PORIFEEA 



PHYLUM II 



Spongiteiikalk of South Germany, the skeletons being almost invariably 

 replaced by calcite. C. rimulosum Goldf. According to Binde also present 

 in the Carboniferous Limestone of Ireland. 



Cnemidiastrum stellatum (Goldfuss). Upper Jiirassic Spongiten- 

 kalk ; Hossingen, Württemberg, a, Sponge, ^/^ natural size ; h, 

 Vertical tangential section, showing radial canalsin vertical clefts ; 

 c, Skeletal Clements, 60/j. 



Fig. 61. 

 ökeleton of Jereica polystoma 

 (Roem.). Upper Cretaceous ; Ahlten, 

 Hanover. 60/. 



Hyalotragos Zittel. Bowl-, plate- or funnel-shaped, with short peduncle. 

 Depression in summit perforated by the ostia of numerous short canals. Ex- 

 ternal surface finely perforate, or covered by a smooth or wrinkled dermal 

 layer. Skeletal elements irregulär, with numerous branches beset with points, 

 but with few spines. Very abundant in Upper Jurassic Spongitenkalk. H. 

 (Goldfuss). 



Fig. 62. 



Chenendoporafungiformis Jjamx. Senonian ; 

 Chatellerault, Touraine. 1/3 natural size. 



.<^ -. ff "^ ^ ** iV \\^ ^ % y&2 



Verruculina auriformis (Roemer). Quadratenkreide; 

 Linden, near Hanover. 2/3 natural size. 



Platychonia Zittel. Leaf- or ear-shaped, irregularly undulating, covered on 

 both surfaces with fine pores. Skeletal elements resembling those of Hyalo- 

 tragos. Upper Jurassic. P. vagans (Quenstedt). 



Jereica Zittel (Fig. 61). Sponge cylindrical, turbinate, pyriform or club- 



