300 POLYZOA INFUNDIBULATA. 



only C. ramulosa, in which the lower parts of the polypidom had 

 become smoother and more solid than the newer growths, a result 

 of age very usual in the species of this family. The Cellepora lasvis 

 of Mr. Macgillivray (Ann. and Mag. N. Hist. ix. 467) is evidently 

 this state of C. ramulosa. 



6. 0. VITEINA, "encrusting, calcareous; cells ovoid, very 

 small, pearly, and irregularly arranged? C. W. Peach. 



Cellepora vitrina, Couch Corn. Faun. iii. 109, pi. 22, fig. 1. 



Hob. "On stones in moderately deep water, not rare. Goran, 

 Mr. Peach. Polperro, Mount's Bay," Couch. 



" This delicate and beautiful species is very small : it is encrusting, 

 circumscribed, and rarely exceeding a quarter of an inch in diameter. 

 The cells are small, transparent, vitreous or pearly in their ap- 

 pearance, and very irregularly arranged. The apertures are very 

 minute and terminal, and cannot readily be seen even with a lens." 

 Couch. 



13. LEPRALIA,* Johnston. 



CHARACTER. Polypidom calcareous or memltrano-calcareous, 

 adnate, crustaceous, spreading circularly, formed of a layer of 

 urceolate cells in juxtaposition, horizontal, and arranged in 

 semialternating rows ; aperture terminal, often covered with an 

 opercular ovary. 



The Lepraliee form thin calcareous crusts, of a white, yellow, or 

 reddish colour, on rocks, shells and sea-weeds ; and it would appear 

 that they are indifferent to the nature or chemical composition of the 

 basis upon which they develop themselves. They are found in the 

 littoral and laminarian zones, as well as in the regions of corallines 

 and deep sea corals. 



* Lepralia " sea-scurf " derived frpm \tirpa, leprosy, and oXiop, marine : an 

 expressive name for the genus suggested by my friend, the Rev. Thomas Riddell. It 

 is synonymous with the " Berenicea " of Dr. Fleming, but not of Lamouroux, and the 

 name belongs of right to the latter ; the more readily yielded up since we find a 

 " Berenicea " also amongst the Medusae. Milne-Edwards names the genus " Escha- 

 roi'des," but neither this nor Escharina, another of his names, can be adopted, since 

 some naturalists use the terminations oide and ina as family appellatives. Moreover, 

 what saith Linnaeus ? " Generic names including other generic names are unworthy 

 of a scientific nomenclature." And again " Generic names ending in oidcs are pro- 

 hibited." See Young's Med. Literature, p. 28. 



