320 
PALAEONTOLOGY OF NEW YORK. 
List of the species of Gomphoceras described in this volume: 
EXOGASTRIC. 
Gomphoceras, Sowerby. 
abruption, Hall . 
Ajax, “ 
cammarus, “ 
eximium, “ 
Fischeri, “ 
gomphus, “ 
impar , “ 
lunatum, “ 
manes, “ . 
mitra, “ 
(?) planum, “ . 
poculum, “ 
potens, “ 
rude, “ 
solidum, “ 
absens, “ 
/«£, “ • 
Illmus, “ 
raphanus, “ 
beta, “ 
oviforme, “ 
pingue, “ 
tumidum, “ 
Gomphoceras, Sowerby. 
clavatum, Hall 
(?) cruciferum, “ 
Conradi, “ 
. Hamilton group . 
Portage group 
Upper Helderberg group, 
Upper Helderberg group, 
. Hamilton group . 
Upper Helderberg group, 
. Upper Helderberg group, 
Hamilton group . 
Hamilton group 
Upper Helderberg group, 
. Hamilton group . 
Hamilton group 
Chemung group . 
Schoharie grit 
. Hamilton group . 
Upper Helderberg group, 
Schoharie grit . 
Schoharie grit 
. Hamilton group . 
Schoharie grit 
Hamilton group . 
Hamilton group 
Chemung group . 
ENDOGASTRIC. 
Schoharie grit 
Schoharie grit . 
. Hamilton group 
"N 
> 
Large, robust 
forms. 
y 
> Slender forms. 
y 
Short, ventricose 
forms. 
y 
Slender, curved 
forms. 
