494 NEW Y0RK STATE MUSEUM 



PLATE 3 



Genus dictyonema Hall 



See plates i, 2, 4, 5 



Dictyonema retiforme Hall 



Page 155 



i Fragment of rhabdosome with typical structure (homoeotype) 

 Rochester shale, Lockport, N. Y. 



Dictyonema blairi Gurley 



Page 171 



2 Fragment of rhabdosome (cotype) 



Choteau limestone, Sedalia, Mo. 



Dictyonema leroyense Gurley 



Page 167 



3 Type specimen (holotype) showing proximal parts 



Onondaga limestone, Leroy, N. Y. 



Dictyonema polymorphum Gurley 



See plate 2, figure 3 

 Page 158 



4 Distal portion of rhabdosome (paratype) 



5 Rhabdosome with central portion. Gufley's type (holotype) 



6 Rhabdosome retaining adhesion disk (cotype) 



Genus palaeodictyota Whitfield 



See plate 6 



Palaeodictyota bella (Hall & Whitfield) 



Page r>o 3 



7 Type specimen redrawn from photograph (holotype) 



All figures are drawn in natural size; the originals of figures i and 

 6 are in the New York State Museum, the others in the National 

 Museum with the exception of that of figure 7 which is in the 

 Ohio state collection. 



