CHEMNITZIA. 439 



N. S. vol. vii. p. 387, that there are two varieties of this spe- 

 cies : one, with turreted subangular volutions, which is consi- 

 dered the type, under the title of Chemnitzia scalaris; the 

 other, with rounded volutions, which has the specific appellation 

 of C. rufescens. I have taken both alive, and could detect no 

 difference in the animals, except in colour; the C. scalaris 

 being sometimes subhyaline frosted- white, at others pale red- 

 brown, and the same variations attend the so-called C. ru- 

 fescens. I may be in error as to the identity of the two, but 

 that is my present impression. 



Aug. 10th, 1853. I took this day at the same haul two 

 shells, one of which proved to be the typical C. scalaris, the 

 other was the form termed by authors C. rufescens ; they were 

 both put in a vase, and being lively, I again saw that their 

 organs were identical. 



CH. ACICTJLA, Philippi. 



? Eulima acicula, Philippi. 



Eulimella acicula, Brit. Moll. iii. p. 311, pi. 98. f. 9, 10 ; and iv. p.283. 

 ? Eulimella affinis, Brit. Moll. iii. p. 313, pi. 98. f. 7 ; aurl iv. pp. 2/4 



&283. 



The animal inhabits a smooth, bluish- white, subhyaline shell 

 of eight flat volutions, and has the reflexed apex, the constant 

 characteristic of the Chemnitzia. The mantle is even with the 

 shell, with the exception of the small fold I have alluded to 

 above ; the body volution does not nearly equal half the entire 

 length of the shell. The general colour of the animal through- 

 out is subpellucid frosted-white, mixed with minute snowy 

 flakes. The head or rostrum is, when fully extended, rather long, 

 very broad, square in front, slightly emarginate in the centre, 

 and on the march is always in advance of the foot, as is usual 

 with the muzzle of the Rissote ; it is grooved the whole length, 

 and the groove is continued towards the neck, just separating 

 the tentacula at their basal centre ; at its upper surface, close 

 to the base, is the orifice of the proboscis. The tentacula 

 diverge almost at right angles, and resemble short, broad, 

 minute leaves, each with an opake white stripe or stamen 

 through the centre ; they bevel to a fine edge, and with their 

 large flexible margins can, like those of all the Chemmtzia, 



