66 



Fig. 20a. Distribution of the decapod crab, Cancer amphioetus, confined to the northern Gulf, 

 intermediate shelf region. Number of specimens at each station circled. 



Clavus roseolus, Hindsiclava andromeda, and Pleuroliria picta; the sca- 

 phopod, Dentalium oerstedii; and the lamellibranchs, Nuculana morella, 

 Glycymeris tessellata, Chlamys circularis, Cardita spurca beebei, Trachy- 

 cardium belcheri, Lophocardium cummingii, Tellina pristophora, and 

 Semele paziana. The abundant and perhaps characteristic species of 



