i 



^ 5*1** #*Vfcr - ^ WvsJtVev *biu**Lu*f. TV ^ 



t cU. . J><n'$*-i, RISSOA. 37 



and from typical specimens of the latter in the British 

 Museum. It is also the R. subcostulata of v. Mohren- 

 stern. I regard R. similis of Scacchi as a small variety. 



1^547 18. R. STRIA'TA*, (Adams.) ^ 4 *" 



Tz^rio striatus, Ad. in Tr. Linn. Soc. iii. p. 66, 1. 13. f. 25, 26. .Z?. striata, 

 F. & H. iii. p. 94, pi. Ixxviii. f. 8, 9. 



BODY white, with a tinge of yellow : pallial filament nearly 

 hyaline, and pendent : snout rather long and narrow : tentacles 

 cylindrical, very finely and closely ciliated : eyes black, almost 

 sessile : foot narrow, truncated in front and slightly auricled, 

 contracted in the middle, and tapering behind to a round point : 

 appendage short, white, and pointed. 



SHELL oblong, inclining to cylindrical, rather solid, nearly 

 opaque, and usually lustreless: sculpture, numerous thread- 

 like spiral striae, of which there are about 20 on the body- whorl; 

 frequently the upper part of each of the three next whorls 

 (and occasionally also the body- whorl) has a few longitudinal 

 slightly flexuous ribs, that reach only about halfway down 

 and are crossed by the spiral striae ; the two uppermost whorls 

 are quite smooth and glossy : colour white or various shades of 

 yellow, with sometimes two indistinct but broad reddish- 

 brown bands round the middle of the last whorl, which do not 

 extend to the mouth: spire elongated, with a blunt point: 

 whorls 6, somewhat compressed, gradually enlarging, the last two 

 being nearly equal in breadth, and the largest occupying about 

 three-fifths of the spire : suture very distinct and rather deep : 

 mouth proportionally small, having a somewhat flexuous out- 

 line : outer lip thin, mostly strengthened outside by a thick 

 rib : inner lip reflected, and forming with the other lip a com- 

 plete peristome : operculum transparent, and delicately stri- 

 ated. L. 0-125. B. 0-05. L = 4 n,m . 



Var. arctica. Without longitudinal ribs or coloured bands. 

 E. arctica, Loven, Ind. Moll. Scand. p. 24. 



V<t*. K^Jlc*M i A *-vUX pTflLTidKoL) S '*& f A, & 



HABITAT: All our coasts, under stones and at the 



base of seaweeds on the recess of spring tides ; living in 



clusters. It inhabits also the laminarian and coralline 



zones ; and I have dredged it in upwards of 80 fathoms. 



* Striated. 



