252 SIR CHARLES ELIOT ON NUDIBRAXCHS [Mar. 17, 



ends ill two ridges near rhinoplioi'es, similaily edged ; front edge 

 of velum similarly edged. Back grey, mottled with a daiker 

 shade, the top of the numerous longitudinal ridges being sprinkled 

 with clear black spots. Underside white. Gills also white. 

 Pvhinophores longitudinally lamellated, grey in colour, and can be 

 contracted or reti'acted, though the pockets do not seem veiy 

 definite or complete." 



The somewhat bent alcoholic specimen measures 3 centim. from 

 head to tail, but would be at least '5 longer if it were straightened 

 out. The breadth of the back is 1'5 centim., of the foot "6. The 

 foot is long and narrow, pointed behind and truncate in front, 

 the corners not projecting. 



No caruncle or nuchal paj^illfe ai'e visible, but it is somewhat 

 difficult to reconcile the head-parts of the preserved specimen with 

 the desciiption quoted above. According to a rough drawing 

 made from the living animal, it would seem that the mantle-edge 

 passes between the rliinophores and foi-ms a sort of velum in front 

 of them; but in the preserved specimen it appears to lie behind 

 them as in an ordinary Pleurophyllidia, and not to pass through 

 them at all. 



The salient character of the genus is that there are no branchise 

 and no trace of a branchial cleft. Lateral lamellae are, however, 

 present. They are situated exclusively on the under edge of the 

 mantle, and not on the sides of the body. They extend fi'om 

 the head to the tail, and are about 30 in number on each side. 

 They are iiregular in size and shape. Some terminate before 

 they reach the mantle-edge, and some run from the mantle-edge 

 only halfway to the body. The genital papilla is 4 millim. and the 

 vent 1"2 centim. from the anterior end of the body. Cnidoplioies 

 are distinctly visible round the edge of the mantle. 



The mouth is ventral, and forms a laige transverse slit, with 

 slight indications of a T-shape. The jaws are yellow, narrow, and 

 united so as to form a shape like a boat. They bear no denticles, 

 but theie are a few irregular coai'se indentations of the edge, due 

 apparently to its being jagged by use. The radula consists of 

 about 30 rows, the formula for each of which is about 50 + 1 + 50. 

 The central tooth consists of a squaiish basal plate with a long 

 cusp, which bears about 10 denticles on each of its sides. The first 

 lateial is laiger than the others and resembles the central tooth, 

 except that the denticles are only on the internal side. The 

 second and thii'd laterals are also denticulate ; the rest appear to 

 be simply hamate. 



This foi-m appears to be intermediate between Pleurolenra, 

 which has neither branchial clefts noi- side lamellas, and Pleuro- 

 phi/llidia, which has both. I have indicated its affinities by the 

 name Fleurophyllidiella. 



ByEOLIDIA MAJOR, n. sp. 



(Bergh, in Semper's Reisen im Arch. Philipp., Malac. Untersuch. 

 vol. iii.' pp. 778^780, 1880.) 



