P H L A S. 



Species 4(1. (Mus. Brit.) 



Pholas Gratana. Plw. testd subpyriformi, brevi, clavM, 

 antice rotundatd, medio canali serrato divisd ; parte 

 antica tenuiter slriatd, parte posticd Iwvigatd, 

 cutieatd, lamind domali unicd, subqwidratd. 



(tKay's Pholas. Shell subpyriform, short, closed, 

 rounded in front, divided in tiie middle by <i 

 serrated canal ; anterior part finely striated, pos- 

 terior part smooth, wedge-shaped, with a single 

 dorsal, rather square jilate. 



Leach. MS. Brit. Mus. 



Hab. ! 



One of the shortest of the closed .■species. 



Species 47. (Mus. Brit.) 



Pholas Bakliii. I'/to. testa subajlindmced, apeitd, antice 

 acunuiMld, margiiie dorsali rejlexo, ante medium 

 latissimd, cosiis distantihxis^ liris imbricatin antice 

 acutiilsculis radiatd ; laminis dorsalibiis ignotx,^. 



Baker's Pholas. Shell subcylindrical, ojien, ante- 

 riorly acuminated, dorsal margin reflected, before 

 the middle very wide, rayed with distant ribs, 

 imbricated by ridges rather sharper towards the 

 front ; dorsal plates unknown. 



? MS. Brit. Mus. 



Hob. ? 



Distinguished by the width ot' the U]ipi 

 valves from other similar species. 



The GOLDEN-TiNTKii I'linLAs. Shrll elongated, 

 subcylindrical, finely inibricately ribbed, a 

 side short, acuminated, widely gaping, mi 

 rather tumid ; posterior side smooth, attenuat. 



("tray. MS. Mus. Brit. 



Hab. ' 



Sp, 



■19. 



(Fig. ((, b, Mus. Brit.) 



I'noLAS iiVoiiiKA. /'/to. tesUl mayiid, solidd, cluund. 

 ventricosissiiad, medio oblique per caitidein, liratam 

 divisd, parte untico-dorsali acute radiatim costatd, 

 et concentria) creberrime imbricatd, mari/ine dorsali 

 duplicatim rejlexo, ad umbones lamind subqnu- 

 dratd crassd tectd ; parte posticd Iwvigatd. 



The EGG-SHAPED Pholas. Shell large, solid, closed, 

 very ventricose, divided in the middle l)y a 

 ridged canal, antero-dorsal part acutely radiately 

 ribbed, and concentrically very closely imbricated, 

 dorsal margin doulily reflected, covered at the 

 umboes with a somewliat square thick lamina: 

 posterior part smooth. 



Gould. .' 



Hab. Monterry. 



Species 48. (Mus. Brit.) 

 Pholas ep.ythr^a. Pho. testd elongatd, apertd, sub- 

 cylindraced, tenuiter imbricato-costald, latere antico 

 brevi, acuminato, late hianti, medio tnnmUnscuh, 

 latere postico Icevigato, atteiiunto. ' 



Autrust 



Species yd. (Mus. Brit.) 



Pholas ligniperda. Fbo. testd tenui, albd, ciintijhrini, 

 siibirregulari, clausd, ante jnedium divisd ; postice 

 nttenuatd ; nmhonibits lamind unicd sid)qvadratd 

 antice acuminata tectis. 



The wood-burrowing Pholas. SIh'U thin, white. 

 wedge-shaped, rather irregular, closed, divided 

 anterior to the middle ; posteriorly attentiated ; 

 umboes covered by a single rather square, ante- 

 riorly acuminated plate. 



187 



