CHROMOBORIDS FROM THE RED SEA. 1C69 



groxmd -colour become yellow, forming an ill-clefined yellow band 

 which passes into white. Round the mantle-edge are two deep 

 coloured bands, the oviter orange-yellow, the inner deep violet. 

 There is a faint line of purple round the extreme edge of the 

 orange-yellow border. Foot and whole under side puie white 

 except that colours of mantle-edge are repeated on the under side. 

 The inner border of violet on upper siu'face is thickened in places, 

 and these points ai'e those where the bending of the mantle-edge 

 is marked when the animal is half contracted. 



"■ Rhinophores brown with clear white lines along the per- 

 forations ; gills grey with white lines on the edge of the folia 

 and specks elsewhere. 



"One specimen measured 5"0 cm.xl"6 cm. when fully ex- 

 tended." 



Four specimens which have assumed a uniform dull plurn- 

 colour, no markings being visible. In most other respects they 

 agree with Mr. Crossland's desciiption of the living animal, but 

 whereas he gives the gills as only 9, I find that they A'ary from 

 12 to 18. It often happens that in Chromodorids with many 

 gills, the smaller plumes are not protruded from the pocket and 

 thus escape notice. 



The labial armature consists of bent rods, but they are not bifid 

 as in other specimens which I ha,ve examined. In two specimens 

 the formula of the radula was 63 x 50.0.50 and 65 X 68.0.68 in 

 the widest rows. The rhachis, as in the specimens described by 

 me from East Africa, beai's triangular thickenings, in which the 

 base is not clearly defined. The first laterals are as usual in the 

 genus, low, flattened, and bearing 4 denticles on either side. The 

 remaining laterals are rather stout, hamate, and bear 6-8 disiinct 

 denticles, The-outermost laterals are lower and bear two or 

 three denticles on the apex only. 



These specimens are referable to Clir. reticulata, but seem to be 

 a distinct variety characterized by (1) the shape of the rods in the 

 labial armature, which are not bifid at the tips ; (2) the pi-esence 

 of thickenings on the rhachis of the radula ; (3) a violet border to 

 the n.antle. As will be seen from my previous descriptions of the 

 species, the coloration is variable. 



Chedmoiioris TiNCTCRiA Ruppell k Leuckart, (PI. LXI. 

 figs. 4 & 5.) 



Ruppell & Leuckart, Neue Wiibellose Thiere dcs Rothen 

 Meeres, p. 32. 



A single specimen described by Mr. Crossland from the life as 

 follows : — 



" Chromodorid in shallow Avater on Zostera growing in sand. 



" Length 88'5 mm. Breadth of mantle 46 mm. 



" Body and foot are narrow, mantle more than ordinarily wide, 

 margin thrown into folds and very mobile. 



" Whole animal soft and smooth-skinned, but there are soft 

 warts on the back, about g inch high and Lroad. Gills in a row 



