OF CONCHOLOGY. 



95 



monilis, but his description better suits Sowerby's shell, for he 

 says it is 4-plaited, while the true monilis is 5 and 6-plaited. 



Sp. 121. 31. chrysornelina, Redf. No relation to M. macu- 

 losa, as Reeve suggests, but more allied to ]\[. multilineata, Sow. 



Sp. 123. M. margarita, Kiener. Repeated from plate 16, 

 but this time with the wrong habitat of "India." In the first 

 description it is correctly given " West Indies." See note on 

 M. Candida, Sow., farther on. 



Sp. 124. 31. serrata, Gaskoin. Quoted only as a MS. 

 name, though Gaskoin's description appeared in Proc. Lond. 

 Zool. Soc. 1849, p. 19. Gaskoin's habitat, Mauritius, is more 

 likely to be correct than Reeve's, which is West Indies. 



Sp. 126. 31. triplicata, Gaskoin. Quoted only as a MS. 

 name, though described in loc. supra cit. It is surprising that 

 Gaskoin's paper is entirely ignored in this monograph. 



Sp. 134. 31. Candida, Sow. I cannot distinguish this from 

 31. 3Iargarita, Kiener. Had either of Reeve's figures of the 

 latter given a front view, it might have aided us to decide. I 

 can see no essential difference between Sowerby's figures of the 

 two species. Kiener's figure of 31. 3Iargarita shows a more 

 rounded shoulder, but his figures of the small species in this 

 genus are very inaccurate, as already remarked. 



Sp. 145. 31. semen, Reeve. Compare with 31. ovuliformis, 

 Orb., which it much resembles. 



Sp. 154. 31 3hliaria (L.). Very badly figured. 



In this monograph Mr. Reeve has added about 40 species 

 (some perhaps doubtful) to those already known, while he has 

 omitted about 50 species previously published, many of the lat- 

 ter being little known or doubtful. Among those omitted are 

 several of the species of Sowerby's monograph. The 31. triti- 

 cea, Lam. (by some referred to 31. e.xilis, Gm.), is among the 

 omissions, and the group of which that species is a representa- 

 tion needs further elucidation. 



Mr. Reeve's monograph enumerates (deducting some species 

 twice figured) 154 species, which only exceeds by 10 the num- 

 ber given in Petit's catalogue of 1851, in Jour, de Conch, ii, 

 pp. 51-56. My own MS. catalogue of published species con- 

 tains upwards of 200 species, but an inspection of the actual 

 types would doubtless reduce this number. When we note that 

 Dillwyn's Descriptive Catalogue, published in 1817, names but 

 18 species belonging to this genus, we have an illustration of 

 the great advance which has been made in our knowledge of 

 the species of mollusca generally, within half a century. 



