Plate 1 - THE FIVE CLASSES OF MOLLUSKS 



GASTROPODA PELEC YPODA 



(a) Turnip Whelk, p. 237. (b) Calico Clam, p. 416. 



CEPHALOPODA 



(c) Paper Nautilus, p. 485. 



AMPHINEURA SCAPHOPODA 



(d) West Indian Chiton, p. 324. (e) Ball's Pacific Tusk, p. 327. 



