REPORT OF THE STATE PALEONTOLOGIST 1902 913 



same. The mouth of the shell is round, the hight and breadth 



being equal. This mutation is but moderately dwarfed and 



very little modified from the ancestral type. All the specimens 



came from Canandaigua lake and Livonia salt shaft. Total 



specimens 6. 



Pleurotomaria itys Hall, mut. pygmaea nov. 



Plate 4, fig. 5 



These specimens are low cones about as high as broad, and 

 consist of three whorls regularly expanding to the body whorl, 

 which is ventricose. The aperture is about as high as broad 

 and circular. The surface of the cast is smooth. The speci- 

 men used for illustration is a small one. It measures % mm 

 in hight and % in diameter. No matter how dwarfed they 

 may be, the specimens retain the ancestral proportions very 

 closely. There is considerable variation in the size of the 

 individuals, from the size of the one illustrated to one half 

 normal size. They occur at Canandaigua lake and the Livonia 

 salt shaft. Total specimens 8. 



Beside the above, there are a good many fragments of 

 Pleurotomaria-like shells, some large, some small. 



Genus loxonema Phillips 

 Loxonema delphicola Hall, mut. moloch Clarke 



Plate 4, fig. 10 



Loxonema moloch Clarke. U. S. Geol. Sur. Bui. 16. 1885. p. 30 

 This species is only moderately dwarfed, being one fourth to 

 one third the normal size. It is a tall spire but never complete 

 in the specimens found. The whorls are flattened and rise 

 rapidly as if to make a very slender cone. It usually measures 

 about 3 mm in diameter. The species is represented sparingly 

 at the Livonia salt shaft and Moscow on Little Beard's creek. 

 Total number of specimens 7. 



Genus tentaculites Schlotheim 

 Tentaculites gracilistriatus Hall, mut. asmodeus Clarke 



Plate 4, fig. 11 



Orthoceras asmodeus Clarke. U. S. Geol. Sur. Bui. 16. 1885. p. 31 

 This tiny species has a needlelike form, tapering to a fine 

 point. The upper surface is marked by regular undulations, 



