34 THE NAUTILUS. 



ON MONSTROSITIES IN CYPEiEA. 



BY ST. G. BYNE, M. SC, F. L. S. 



It will doubtless interest those who make a special study of 

 the genus Cypr^a if I enumerate some of the monstrosities which 

 occur in the collections of myself, friends and museums. It is 

 very remarkable that so many species inhabiting the Islands of 

 New Caledonia should have their extremities pinched, and ab- 

 normally prolonged or rostrated. Many of these have had 

 definite varietal names assigned to them by Dautzenberg and 

 others. I have included dwarf adult specimens which seem to 

 be especially abundant in the Andaman Islands judging by a 

 large consignment which I have examined from that locality. 

 One sometimes meets with shells which have been damaged and 

 repaired by the animal. 



C. tigris L. (a) A few examples from Sarawak abnormally 

 flattened and gibbous. (b) Having a strong ridge running 

 longitudinalh' over the dorsal surface. This seems to be due 

 to one half being more thickl}^ coated with calcium carbonate 

 than the other, (c) Miss A. Foster of Bournemouth possesses 

 two small unusually heavy examples. The dorsal surface is 

 coated with a thick greyish-green enamel. The anterior ex- 

 tremities are pinched up and strongly rostrated. 



C. capiitserpentis L. Having a small dark brown protuberance 

 upon the base. 



C lurida L. Two specimens from Naples whose extremities 

 are curiously pinched and flattened out, and resembling New 

 Caledonian forms. 



C. arabica L. var. niger Roberts. This rare black variety 

 from New Caledonia is well known to collectors. 



C. arabica L. Mr. C. P. Richards of St. Anstell possesses in 

 his collection a remarkable adult example, with greatly produced 

 spire, the mouth reduced one third its normal length by some 

 hard foreign substance being wedged in and coated over with 

 enamel by the animal, thus altering the shape of the shell evi- 

 dently to accommodate itself to the new conditions. 



C. histrio L. Although many consider this to be a variety of 

 C. arabica, yet I am of opinion that it should be raised to spe- 



