RISSOA. 



The Turbo striatulus of Linne appears to have been 

 Parthenia varicosa of Forbes = Chemnitzia pallida, Phi- 

 lippi. Da Costa described and figured the present species 

 as T. carinatus ; and I would have adopted that original 

 and expressive name, were it not for the consideration 

 that, no subsequent author having done so, I have no 

 wish to be singular, or to make any unnecessary change 

 in the nomenclature. Turton called this shell T. monilis, 

 Michaud R. cochlea, Philippi R. labiata, and Leach Per- 

 sephona brevis. 



2. R. lac'tea*, Michaud. 



E. laciea, Mich. Descr. esp. Kiss. p. 9, f. 11, 12; F. & H. iii. p. 76, pi. 

 lxxix. f. 3, 4. 



Shell oval, compressed towards the mouth, rather thin, 

 semitransparent and somewhat glossy when living, opaque and 

 lustreless when dead : sculpture, slight and gently curved lon- 

 gitudinal ribs, which are seldom continued below the periphery 

 and are crowded near the outer lip ; there are about 20 on the 

 last and 10 on the penultimate whorl ; these ribs are crossed 

 by fine spiral striee, 15 of which are on the last and 9 on the 

 penultimate whorl ; the ribs are more prominent than the 

 striae, the points of intersection never being nodulous ; there 

 is sometimes, but rarely, a slight labial rib ; the first two 

 whorls are perfectly smooth : colour whitish, with a faint tinge 

 of yellow, in dead shells milk-white : spire abruptly pointed : 

 ivhorls 5-6, moderately convex, compressed towards the front ; 

 the last composes nearly three-fourths of the shell, and the 

 first two are minute : suture slight but distinct : mouth oval, 

 produced and angulated above, spread out below, not expanded 

 outwards ; inside plain : outer lip rather thick : inner lip broad, 

 reflected over the pillar, and united with the outer Up at the 

 upper corner of the mouth, where there is a considerable 

 thickening : operculum pale horncolour, with a short spire, 

 and not conspicuously striated. L. 0-233. B. 0-15. 



Habitat : Under stones at extreme low water of 

 spring tides, and thrown upon the beach : St. Aubin's 



* Milk-white. 



