CHAP. III. THE PYRULIN^!. 83 



Analogies of the EBURNIN.E. 



Struthiolaria. Shell nodulous or muricated. MURICID.K. 



Eburna. 



Pseudoliva. Oval, smooth. 



This comparison explains the relation which Struthio- 

 laria has been thought to have, by some writers, to 

 the murexes : the smoothness of all the Eburnince is 

 remarkable, and is no doubt an indication of their re- 

 lation to the typical Turbinellidts. The lobe of Cyllene, 

 again, is borrowed, as it were, from the Strombidte, in 

 order to show the analogy of both. The excessive short 

 spire of the two next is explained on the same ground ; 

 while the irregular spire of Latiaxis is to be found in 

 no other shells of the zoophagous tribe, than those of 

 the typical volutes or melons. 



(72.) In the Pyrulince, or the fourth division of the 

 family, we place the greatest part * of those exceedingly 

 diversified shells forming the genus Pyrula of modern 

 writers. They are so designated from their generally 

 being pear-shaped ; the basal portion representing the 

 stalk end of that fruit, and the spire and whorls the 

 other. This comparison, indeed, is so far apt, that it 

 gives a very good idea of the shape most prevalent 

 among them, notwithstanding the great differences they 

 present, in other respects, among themselves. This is 

 one of the few natural groups in malacology, of which 

 we shall endeavour to give as complete an analysis as 

 a long and protracted investigation of their relations 

 will permit. We have invariably found, that where 

 natural assemblages such as this, in any division of 

 the animal kingdom, contain a great number of subor- 

 G 2 



