354 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



CoKYPHELLA Falklandica, n.sp. PI. XXVIII, Fig. 7. 

 Cf. C. Uncata, A. & H. : Monograph., Fain. 3, pi. xvi ; Vayssiere, 

 Ann. du Mus. d'Hist. Xat. do Marseille, p. 73, 1886. 



Three specimens seem referable to this form. The largest is 

 16 mm. long, 9 wide across the cerata and pericardium, with a bare 

 space on the back measuring 9x4 mm. In colour they are 

 uniformly yellowish or greenish white, with traces of white liues on 

 the tail of one specimen. 



As preserved, the animals are probably less elongate than in life. 

 The head and foot are broad ; the tail short, but distinct and without 

 cerata ; the margins of the foot and mantle well developed ; the anterior 

 margin of the foot slightly bilobed, and grooved with short but distinct 

 projections at the corners. The rhinophores and tentacles are thick, 

 the latter set rather far back, in many cases showing artificial wrinkles, 

 but not really perfoliate. The largest cerata are inside, as much as 

 6mm. long; the outermost are mere tubercles. Xo clear arrange- 

 ment in transverse rows can be made out, but the cerata are set all along 

 the side of the back in 4-6 irregular longitudinal lines. They vary 

 greatly in transparency ; the hepatic diverticula within them, when 

 visible, are yellowish, smooth, and extend almost to the tip. The 

 larger cerata are somewhat sunken in the middle and pointed at the 

 tip, but not very symmetrical in shape. The genital orifice is just 

 under the rhinophores ; the anus lies about half-way between the 

 head and tail, immediately under the mantle-margin. The eyes are 

 minute and invisible externally. 



The jaws have a bright metallic lustre, and bear at least 10 rows of 

 small pyramidal denticles. The radula consists of 11-12 rows, each 

 containing three teeth of the shape usual in the genus. The median 

 tooth (Fig. la) has a horse-shoe base and a central cusp with 6-8 

 lateral denticles. The usual number is 7, but they vary both in 

 number and shape. On some teeth they are much more curved than on 

 others, and their edge is sometimes finely striated. In all cases there 

 are two denticles rather high up, but sometimes the cusp rises smooth 

 and clear-cut above them, in others it bears an extra pair of denticles. 

 The lateral teeth (Fig. Ih) are thin and straight ; the base is hollowed 

 out, and the tip is sometimes bent a little back. They bear 14-16 

 (usually 14) saw-like denticles on the inside. This serrulation is 

 often irregular and rudimentary, ill-formed denticles being found 

 among more perfect ones. 



This form is nearly allied to several species from the Xorthern 

 Atlantic and Mediterranean, and may even be identical with C. lincata, 

 but the colour and markings of the living animal are unknown, and 

 I register it provisionally as a new species. 



Tkitonia Challengeriana, Bergh. 

 Tritonia Challengeriana, Bergh : Challenger Reports, vol. x, pt. 26, 

 Xudibranchiata, p. 45. 

 Eight specimens from the Falkland Islands. The notes allude to 

 one being red and one white. Most of them arc obviously bent and 



