2IO Mr. Cosmo Melvill 07i the 



normally only a third or quarter of that extent. Again^ 

 0. caiirica has a very small variety, not much more than 

 ^ inch, and many other kinds vary in a similar manner. 



{e) Pattern. — This has already been spoken of. The 

 design of the adult Cowry is, as a rule, wonderfully uniform. 

 Occasionally as in C. tigris, var. iontJiodes and a form of 

 G. /j'/Lv,\a.rgQ triangular blotches cover the dorsal surface, and, 

 as in stolida var., gelashna certain spots, present in the type, 

 disappear. Again, the pattern is often blurred over by the 

 last deposit of colouring matter,as in C.Arabica var. niger, the 

 black variety of mappa, C. Jielvola var. Mascarena, and others. 



(/) Dentition is the least variable point, and the greatest 

 holdfast in detecting a species, in nine cases out of ten. 

 But in C. stolida, G. staphylcBa, etc., much inconstancy 

 is shown, so even this cannot always be relied upon. 



No hybrids appear to have been ever detected, unless, 

 indeed, some of the nearly akin forms we are noticing in 

 this paper prove such ; but these are questions for the future 

 scientist to decide. It is to be hoped now, with the 

 establishment of Marine Biological Laboratories, we shall 

 be able in the course of a few years to learn something more 

 definite of the life-history of these creatures, whose external 

 skeletons are but an insufficient sign-post for guidance, and, 

 till this achievement, we must be content with only very 

 imperfect knowledge of the affinities and relationships of so 

 interesting a group as Cypraea. 



(XIII.) Notes on certain species and proposed varieties. 



Cypraea inappa (L.), (Type, cf. Reeve, Conch. Icon., 

 pi. vi., f i8 ; Perry, Conch, pi. xxiii., f. i, as alga). Three 

 well known varieties of this well known Eastern shell occur. 



{a) panerythraiyds. nov.) ; cf. Sowb., Thes. Conch., pi. v., 

 f. 28. Shell uniformly suffused with pale red or deep rose, 

 which is generally deepest at the base. Teeth plain, or 

 only slightly tinged with yellow. N. Caledonia, etc. 



