CHAP. III. THE PYRULIN^. 87 



typical examples of Myi-istica; while the well-known Fy- 

 Tula melongina, from having a much wider aperture, puts 

 on something of the characters of Rapella. There are, 

 in fact, many other species : hut of our last genus Cuma 

 there is only one that we are yet 

 acquainted with, which can be 

 termed truly typical : this we have 

 named C sulcata {fig. 4.). Its 

 characters may be simply de- 

 scribed as shorter, but more gra- 

 dually fusiform, than the last, — 

 the middle of the pillar being 

 crossed by a single transverse and 

 very prominent fold : this cha- 

 racter is altogether without pa- 

 rallel in this sub-family ; and dis- 

 tinguishes this type, at the first glance, from all the 

 others : the form of the shell is much more slender 

 at its two extremities than any of the Myristicce, and, 

 although much shorter, its aspect at once reminds us 

 both of Fusus and of Flkatella. Nevertheless, although 

 this shell, from having a distinct plait upon the pillar, 

 seems to us the true type of the connecting genus be- 

 tween Pyrula and Fusus; it is quite evident that 

 the common Pyrula carnaria *, and the more rare P. 

 canaliculata Sw. t, so closely agree with the foregoing 

 definition, that but for their smooth pillar, and the 

 greater elongation of their base, they would both enter 

 into the same genus. In one point of view, it may be 

 said that these very characters, which preclude their ad- 

 mission into Cuma, may yet bring them within the con- 

 fines oi Pyrula; so that, being followed by such shells as 

 P. carica J, &c., we come again to the typical genus with 

 which we began the series ; and yet, on the other hand, 

 we may suppose these dubious species, to form the first 

 genus of the FusincE, connecting that sub-family with 

 the Pyrula' by means of Cuma. In either way, however, 



« Ency. Meth. pi. 424. fig. 3. t Il^>d. pi. 424. fig. 2. 



t Ibid. pi. 433, fig. 3. 



