ZOOPHYTOLOGY. 283 



doubt that the present form is the same as M. irregularis, 

 D'Orbigny (' Amer. Mend./ pi. viii, tigs. 5, 6), with which 

 may also, perhaps, be associated the same author's M. simplex 

 (ib., figs. 7, 9). The cells are for the most part oval, 

 not contiguous, very irregular in size and position. The 

 margin is granular, and wholly unarmed, and there is no 

 appearance of avicularia in any part of the two or three 

 patches submitted to examination. 



The following may be taken, I think, as the synonymy of 

 this protean species : 



M. Lacroivii, Aud. ; Bk.; Aider. 



M. irregularis, M. simplex ? D'Orb. 



Flustra distant, Hassall ; Jolmst. ; W. Thompson (Belf.) 



3. M. Imeata, Linn, (sp.) 



4. iJf. C'alpensis, Bk. 



Gen. 10. Lepralia, Johnst. 

 1. Armatse. 



a. With oral spines. 



1. L. discoidea, Bk. 



For a full account and corrected character of this species, 

 see Mr. Hincks's observations, supra. 



2. L. innominata, Johnst. 



3. L. radio t a, Moll. 



I have some doubts whether these two may not, strange 

 as it may seem, prove to be varieties of each other, in which 

 case Moll's name will, of course, have precedence. 



4. L. porcellana, n. sp. PL XXXI, fig. 3. 



Cellulis latis, subrhomboideis, immersis, superfine rugosd, granulosa, 

 nitidd : orijicio supeme rohtndato, infra coarctato, labio inferiori integro, 

 superiori spinis tribus, scepius absenlibus, munito ; aviculario, mandibulo 

 trianguluri acuto supeme et ad externuum speclante, ulroque lateri cellules 

 posilo. 



Cells broad, ovate or rhomboidal, deeply immersed ; surface uneven, 

 bossed, granular, polished, porcellanous ; orifice rouuded above, contracted 

 below, with an entire lower lip, and three marginal spines above, often 

 absent or to be found only on the younger cells ; a raised avicularium on 

 each side of the cell, about the middle ; the mandible triangular acute, point- 

 ing upwards and outwards. 



Hab. — Madeira, on shell, /. Y. J. 



The remarkably polished or porcellanous surface gives 

 the patches formed by this Lepralia so peculiar an aspect, 



