EISSOA. 375 



group, but if observed attentively, it will often assume the 

 more pointed termination of the Rissoee ; it is also, as in 

 them, a little constricted below the anterior end, and has on 

 the sole a slight, mesial, longitudinal depressed line. 



The next species is the so-called Cerithium reticulatum, but 

 as there is already in the Rissoidean list the R. reticulata of 

 Montagu, the specific title should be changed : it is proposed 

 to substitute vulgatissima, an appellation of great significancy 

 in respect of this animal. 



** Elongato-turrita. 



R. VULGATISSIMA, nobis j Da Costa. 



Cerithium reticulatum, Auct. 



-, Brit. Moll. iii. p. 192, pi. 91. f. 1, 2; (animal) 

 pi. I.I. f. 2. 

 Murex reticulatus, Mont. 



Animal occupying an elongated dark brown shell of 10-12 

 spiral volutions, furnished with close-set costellse and spiral 

 striae, which, at the point they cross the riblets, exhibit the 

 moniliform sculpture of four points on each. Mantle plain, 

 forming a small dilatation to correspond with the shell. The 

 head is rather a long muzzle, anteally vertically cloven, and 

 marked with nearly black, thickly-set transverse bars. The 

 buccal apparatuses strictly Rissoidean, composed of a pair of 

 jaws and lingual riband, wliich are perfectly white, supported 

 by pinkish corneous plates, which can, through the tenuity of 

 the under part of the muzzle, be seen in action, as in the 

 Rissoce. The animals are very voracious ; we observed many 

 sucking in ropes of molluscan mucus with great gusto and 

 avidity. The tentacula are rather strong and short, not very 

 pointed, yellow, and irregularly aspersed with flake-white and 

 lead-coloured blotches. Eyes on distinct but very short 

 pedicles at the external angles. The foot is rather short, 

 truncate in front, very slightly auricled, and constricted 

 anteally, but well labiated, and tapers to a moderately-pointed 

 termination; on the upper surface pale yellow, mixed with 

 darkish smoke-coloured points; on the under part, or sole, 

 with longitudinal patches on each side of the palest lead-colour, 



