224 PROCEEDINGS OF THE ACADEMY OF [1894. 



Murex brevispina, Lam. Mnrcx (tdimcoxjylnosns. Beck. 



" nigrhpinosHS, Reeve. " brandaris, Linii. 



" ternispina, Lam. " rufns, Lam. 



" tenuispina, Lam. " pllclferas, Howl). 



" tribulus, Linn. " hfevlfro)i.^, Lam. 



Eupleura caudata, Say. (Fis. 2.) 



The nucleus of this species consists of one and a half semitrans- 

 parent, glossy whorls; there is no indication of a carina upon them; 

 the tip of the first whorl is immersed in the succeeding whorl and is 

 l)ent down to one side; the first half of the whorl, 

 looking at the lateral outline, is about half the 

 size of the portion succeeding it; the whorls are 

 well-rounded and full; the sculpture, consisting of 

 spiral and longitudinal lines, begins very faintly 

 on the latter part of the second whorl and gradually 

 ^' "' grows stronger as the shell increases in size; there 



are about fourteen longitudinal lines to each whorl, after leaving 

 the nucleus, which are crossed by two heavy spiral lines. 



I have seen foui- specimens of this species, and the characters ex- 

 pressed above appear to be tolerably constant. The present species is 

 the only one of this genus, which I have been able to examine. It 

 will be interesting to know just how variable or constant the nuclei 

 are in the different species. This is a field which needs a great 

 amount of original investigation. 



