ELIOT : NTJDIBRANCHS FKOM THE PACIFIC. 235 



On the under side of the dorsal process, about 1 mm. from its end 

 and 4 mm. from the body, is the branchial pocket, from which project 

 12 simply pinnate branchiae, surrounding a large anal papilla. They 

 are all united at the base, and completely extruded in a bunch from 

 the pocket, which has a simple round rim, not at all raised. It is not 

 clear that the branchiae could be entirely reti'acted into it. 



The mouth, on each side of which is a distinct conical tentacle, 

 opens into a wide, much puckered, and laminated cavity. The labial 

 armature consists of two yellowish plates. Under the microscope 

 they have the appearance of a tessellated pavement, and are seen to 

 be composed of small rods with thick bent heads, as in Bergh's plates 

 of Ch. Semperi (Semper's Reisen, Heft x, pi. li, fig. 34). The radula 

 also resembles that of Ch. Semperi. The teeth are bifid, but the two 

 prongs are rather longer and more curved. The innermost teeth have 

 an accessory denticle, and the outermost, which are fairly tall and 

 straight, have two or three. There are 58 rows, and the maximum 

 number of teeth on each side is about 80. There is no stomach 

 outside the liver, which is purplish, and rounded before and behind. 

 On issuing from the liver the intestine runs along the top of it on the 

 right-hand side, and then turns downwards. 



No armature was found in the reproductive organs. The central 

 nervous system is as usual ; the eyes large and black.- A small 

 flocculent mass above it is probably the blood-gland. 



Hexabranchus (?) AnAMSir, Gray. 



HexabrancJius Adamsii, Gray: H. & A. Adams, Gen. E.ec. Moll., 

 vol. ii, p. 59, pi. Ixiii, fig. 9 ; Gray, Guide Syst. Dist. Moll. Brit. 

 Mus., p. 210 ; M. E. Gray, Figures of Molluscous A.nimals, 

 pi. ccxix, fig. 1. 

 One specimen, with a length of 21 ram. and a breadth of 5 mm., and 

 therefore unusually long and narrow. The colour is whitish, with 

 a narrow, bright light-red border, inside which, but hardly connected 

 with it, are a row of similarly coloured blotches, each having, in the 

 centre, a deep bright-red dot. Then follows a clear white zone ; 

 then, down the centre of the back, two rows of similar blotches, with 

 dots, growing larger towards the branchiae. There are two rows of 

 bright-red dots, without blotches, on the under side, one at the 

 junction of the mantle and the foot, the other lower. The sole is 

 colourless, and allows the intestines to be seen through it. The 

 mantle-edge is folded against the sides of the body, but, when 

 stretched out, measures 3 mm. at most. The rhinophores are large 

 and straight, with tall stalks. The laminated part is bright red. The 

 margins of the pockets are not raised. The branchiae are as usual 

 in the genus, eight in number, whitish, with remains of bright- 

 red lines. 



The tentacles are large, flat, folded in two, the edges indented, but 

 not very deeply. The labial armature consists of two greyish plates 

 composed of minute rods, somewhat bent, and of rather varying 

 shape. The radula consists of 30 rows, containing 35 or 40 large 

 hamate teeth on each side of the bare rhachis. They are yellowish, 



