316 MURICID.E. 



1. Trophox murica'tus_, Montagu. 



Mi'.rex miiricatus, Mont. Test. Br. (i.) p. 262, t. 9. f. 2. T. mnricaf?fs, 

 F. & H. iii. p. 439, pi. cxi. f. 3, 4, and (animal) pi. 8S. f. 5, as T. ecki- 

 nati'./n. 



Body whitish : paUlcd tuhe short [often extending beyond 

 the canal of the shell (Clark)] : head inconspicuous : tentacles 

 rather long and tapering to a point ; two-thirds of each on 

 the lower side are more than twice the thickness of the upper 

 portion, owing not only to the addition of the eye-stalk, hut 

 to the tentacle itself being broader at the base : et/es small and 

 black : foot rather long and expansile, squarish in front with 

 a gently curved outline, somewhat angulated at the corners, 

 and bluntly pointed behind ; sole shghtly grooved : verr/e large, 

 sickle-shaped. 



Shell slender, not very solid, nearly opaque, and having 

 scarcely any gloss : sculpture, numerous longitudinal ribs, 

 which (especially on the body-whorl) are often laminar, and 

 more or less varicose ; these ribs usually do not extend to the 

 infrasutural part of each whorl; there are also thread-like 

 spiral ridges, about 12 on the body- whorl, 4 or 5 on the next, 

 and gradually lessening in number towards the apex, which 

 is microscopically and closely striated in the same direction ; 

 the points of intersection between the longitudinal and spiral 

 sculpture on the crests of the ribs are tubercular, or corru- 

 gated, sometimes prickly like the vaulted scales on the ribs of 

 many species of Pecten ; the lines of growth are minute and 

 irregular : colour yellowish-white, or fleshcolour tinged with 

 reddish-brown : sjyire extending to an abrupt point ; apex 

 globular, twisted either on one side or downwards : ivhorh 

 7-8, cc^vex and rather tumid, angulated and flattened on the 

 upper part, so as to give a turreted aspect to the spire ; the 

 last occupies nine -fourteenths of the shell : suture wide and 

 deep : mouth proportionally small, triangularly oval, expanding 

 outwards ; length two -sevenths of the shell : canal semitubular, 

 inchning a little to the left, and terminating in a deep and 

 obliquely rounded notch ; externally it is devoid of any sculp- 

 ture except the marks of growth : outer lip prominent, con- 

 tracted above, and abruptly incurved under the periphery ; 

 edge thin, scalloped by the spiral ridges ; inside, or throat, 

 finely plicated or furrowed : inner lip reflected over the pillar 

 and canal, continuous with the outer lip : pnllar curved, broad, 



* Muricated or pricklv. 



