MURES. 



Species. 



FIRST DIVISION. (Three varices.) 



Sect. I. Spines and long canals. 



1. TENUisriNA, f. 7, Lamarck. — Testa spinoso-trivaricosa, 

 griseo-fulva, inter varices quadritnberculata, spiraliter crenula- 

 tim costata, interstitiis crenulatis ; sjiinis ad varices curvis, 

 ninuerosis, radiantibus, ad canalem decenis, elongatis, ele- 

 ganter curvis, interstitialibus novenis retrorsim curvis. — The 

 varical margin of the canal is beautified by a double row of 

 elegantly curved spines, ten of which are extended outwards, 

 and nine bent inwards over the canal. 



2. scolopax, f. 8, Dilhvyn. — Testa superne ventricosa, 

 lrevis vel leviter spiraliter lirata, spiraliter castaneo-lineata, 

 varicibus ad anfractus brevispinosis, ad canalem elongatis, 

 eleganter curvis, senis et quinis ; apertura majuscula, intus 

 castanea. — The spines on the body are rather short and 

 arched ; those on the canal are curved, as in tenuispinosus, 

 six outwardly and five inwardly over the canal. Our fig. 8 

 represents an unusually smooth specimen, as the species is 

 sometimes sj>irally ridged. 



3. tribulus, f. 3, Linnceus. — Testa spinoso-trivaricosa, 

 spiraliter crenato-costata, inter varices trituberculata, inter- 

 stitiis nonnumquam maculatis ; spinis ut in M. tenuispina, 

 sed paucis, brevioribus, ad caudam senis aut quinis. — The 

 spines are arranged as in the preceding, but are fewer and 

 shorter, particularly on the canal. The spiral ridges and 

 longitudinal tubercles are crenulated in the same way, and 

 sometimes show spotted articulations. Fig. 4 is the rather 

 short-spined and colour-banded variety named aduncospino- 

 sus, by Reeve. 



4. concinnus, f. 5, Reeve. — Testa M. tribulo similis, spinis 

 brevioribus, lineis spiralibus rubro-castaneis super liras de- 

 currentibus. — Distinguished from the short-spined, banded 

 variety of M. tribulus by the clear red-brown lines running 

 on the top of the spiral ridges. 



5. Cabrittit, f. 137, Bernard!. — Testa spinoso-trivaricosa, 

 subrosea, lata, subdepressa, spiraliter prominente lirata, inter 

 varices trituberculata, varicibus pone excavatis spinis brevibus 



