3PR0CEEDINGS OF THE CONCHOLOGICAL SOCIETY. 



373 



mens, but in this one especially so with a glassy glaze on and 

 between the ribs. The shell looks especially well developed and 

 perfect. The colour is a delicate creamy or warm ivory white. 

 The brown marking at the ends of the ridges and on the 

 tubercles of the keel is more delicately applied and outlined 

 than in No. i, and at the back for about two centimetres from 

 the keel is faintly expanded on the shell so as to look like a film 

 of epidermis. 



It would not be fair to occupy so much space with the 

 description of only a peculiar specimen of so common a shell, 

 unless in the hope that so far from being an abnormal or 

 deformed individual this may really be an exceptionally adult 

 and well developed shell such as may have sheltered the ova of 

 an especially lovely lady mother of Argonauts who passed a long 

 life, well nourished and undisturbed, in some protected lagoon 

 where the sea was always smiling. Still, it is only fair to add, 

 that amongst very many specimens in many collections the 

 writer has never seen a shell like this one ; or — one in itself so 

 perfectly beautiful. 



[Dr. Gould, quoted in "Tryon's Manual," I., page 136, gives 

 measurements of the largest known shell as equal to 30 centi- 

 metres long by 19 centimetres high]. 



