F1SSURELLIDJE. 193 



margine laqeuato ; foramine parvo, rotundo, supra medium posito. 

 06s. This rough shell was distinctly figured in 'Conchological Illus- 

 trations/ f. 75, under the above name, which has the priority over 

 F. salebrosa. 



63. dubia (f. 208), Rve. — Irregulariter oblongA, depressa, ter- 

 minis elevatis, fusca, griseo obscure radiatim fasciata, irregu- 

 lariter costis rotundis scabris imbricatis radiata; foramine oblongo, 

 infra medium posito. 06s. I have some difficulty in placing this 

 and the preceding species. It has been suggested to place them 

 with F. pustula and fascicularis under the genus Clypidella, but, 

 although they resemble those shells slightly in form, perhaps acci- 

 dentally so, the other characters do not correspond. 



64. Jukesii (f. 147, 148, 149),ift>e. — Ovali, subelevata, albida, 

 striis elevatis concentricis et costis angulatis acute imbricatis 

 radiantibus cancellata ; costis nonnullis exstantibus ; intus alba ; 

 margine duplicatim dentato ; callo griseo poslice subtruncato ; 

 foramine quadrato; margine griseo, antice declinato, supra medium 

 posito. 06s. This species is subject to considerable variations 

 in elevation, sculpture, etc. ; but the characters pass from one va- 

 riety to another interchangeably. The foramen is square, edged 

 with black, and placed considerably above the middle. F. 147 is 

 F. Jukesii of Reeve. ; f. 148 is F.fimbnata of the same author; 

 f. 149 is named in the same work as F. auslrulis of Krauss, 

 but it is quite distinct from that species. 



65. Sihboldii (f. 138), live. — F. Jukesii simili, sed costis 

 quinque posticis, distantibus, valide exstantibus. 06s. A variety of 

 F. Jukesii occurs, which has some of the front ribs very prominent, 

 and that variety presents an approach to this species, in which the 

 five principal ones are very prominent indeed and strongly imbri- 

 cated. This being a Chinese shell, is an additional reason for dis- 

 tinguishing it from its Australian analogue. 



66. calyculata (f. 126, 127), Sowb. — Oblonga, postice ex- 

 pansa,antice lateribus compressis, apice elevato,costellis tribus mag- 

 nis imbricatis posticis alteris minoribus et interstitialibus minimis 

 radiata, liris concentricis cancellata ; intus alba ; foramine subro- 

 tundo, multo ante medium posito, intus callo septum formante 

 marginato. 06s. lleraarkable for the internal callus near the 

 apex, which forms a kind of septum with a pit behind it, and the 

 three prominent notched ribs. 



67. vaiucosa (f. 52, 53), Sowb. G. B. 2. — Oblonga, conica, 



