UNIVALVES. TROCHUS. 1 ] 5 



ther-of-pearl appearance when uncoated ; others have only 

 their aperture pearly or silvery; and a few exhibit a bronze- 

 like hue. 



There are several reverse varieties of Trochi : the prin- 

 cipal are — T. perversus, T. undulatus, T. ventricosus, T. 

 annulatus, and T. pusillus; the latter of which is found 

 within larger shells, in the sands of India. 



The T. flumineus is a river species, and the T. horten- 

 sis is an inhabitant of the gardens in warmer climates. 

 The T. terrestris is also a land species, and frequents the 

 mountains of Cumberland, 



The following are the places which yield specimens of 

 the Trochi: viz. Asia, Africa, America, Friendly Isles, 

 New Zealand, Red Sea, Mediterranean, the European and 

 British seas, &c. 



TROCnUS— Top-Shell. 



Division I. — Shell umbilicated, erect. 

 Family 1. — With the pillar and umbilicus smooth. 

 Niloticus — Large-marble. Fan alum — Pagoda. 



Conus — Conic, Strigosus — Black-lipp'd. 



Spinosus — Thorny. Dubius — Doubtful. 



Jujubinus — Mottled. Depressus — Depn 



Concavus — Concave. Laevis — Smooth. 



Vernalis — Green. Groenlandicus — Greenland. 



Conspersus — Poppy. *MagLis — Tuberculated. 

 Ochroleucus — Whitish- brown. Variegatus — Variegated. 



Stellatus — Starred. Afer — Grey-marble. 



Spengleri — Spengler's. Muricatus — Prickly. 



Costatus — Ribbed. Roseus — Rose-colour' d. 



Inaequalis — Unequal. *Fatholatus — Tumid. 



Regius — Royal. Scaber — Rough. 



Verrucosus — Warty. Quadratus — Square-spotted, 



Radiatus — Radiated. Croceus — Saffron-colour' d. 



Wmdis— Green. Y-Avius— Varied. 



