25 



Brocch. — Tritonium incrassatum, Mull — 

 Nassa incrassata, Flem. — Planaxis minuta, 

 Risso. 

 Animal white, mottled ; tentacula long, far 

 apart, bearing the eyes towards their middle exter- 

 nally. 



Common in deep water. 



XLI. Murex, Lin. 

 1. erinaceus. 



Murex erinaceus, Lin. — " Murex decussatus, 

 Gmel.'" ( Menke ) —Triton erinaceum, Flem. 

 Animal white, speckled with grey ; tentacula ap- 

 proximating, triangular; eyes on their upper sur- 

 faces externally, and not far from the tips; male 

 organ lanceolate. 



In deep water. Frequent. 



XLII. Fusus, Lam. 

 Subgenus, Fusus. 

 1. antiquus. 



Fusus antiquus. Lam. — Murex Antiquus, 

 Lin. — Murex despectus, Penn. 



13. Fusus norvegicus, Turt. — " Strombus 



norvegicus, Chemnitz^'''' Menke. 



Animal white, tentacula triangular. 



The normal form of this species is most frequent 



about Port Erin, at the southern extremity of the 



island ; the var. |8. on the scallop banks of the north. 



The latter never attains the size of the former, is more 



coarsely striated, and has the interior of the aperture 



c 



