OF CONCHOLOGY. 185 



5. B. aruanum. Linne's original description and references 

 to figures in Rumphius and Gualteri apply to the same species 

 described by Lamarck as Pyrula carica, and by myself as B. 

 spinosum. 



6. B. eUeeans. This shell is usually confounded with the 

 preceding, but it is evidently distinct, and inhabits the southern 

 coast exclusively, whilst the aruanum ranges as far north as 

 Massachusetts. It is represented in Montfort's figure ; in 

 Reeve's Mon. of Pyrula, pi. 5, fig. 16 ; in Chemnitz, fig. 744, 

 756 — 7 ; Tuomey and Holmes, Post-Pliocene of S. C, pi. 11, 

 fig. 1 ; Kiener. Mon. of Pyrula, pi. 3, fig. 1. 



7. B. maximum. Chiefly distinguished from Tritonis by the 

 absence of spines in the adult. 



8. B. spiniger. In this species the armature is similar to that 

 of Sycotypus coro7iatus, and forms a connexion between the tu- 

 berculated and spinous shells of the two genera. 



9. B. adversarium. This species is the only reversed form 

 with tubercles instead of spines. 



10. B. striatum. This shell, though young, is a very distinct 

 species ; even the just excluded young of Sycotypus canalicu- 

 latus can be easily recognized, so as not to mistake it for that of 

 any other species. 



11. B. nodulatum, Conrad. In this, the oldest known spe- 

 cies, there are tubercles and no channel ; so that Sycotypus 

 dates no further back than the Miocene, which contains seven 

 species. 



S. canaliculatus. As Dr. Gould remarks that there is some 

 uncertainty of the species described by Linne under this name, 

 I would refer to the Syst. Nat., 1758, where the habitat Canada 

 is given, and the reference to Gualteri, pi. 48, removes all 

 doubt. That is an excellent figure of the shell known as 

 canaliculatus, and is placed by Linne in the genus 3Iurex. 



