Chromodoris.] GASTROPODA. 573 



The other laterals are denticulate only on the outer side, the number of 

 denticles being at least 6. Near the end of the rows the main cusp 

 diminishes and the first denticle increases, so that the tooth appears 

 bifid. (Eliot.) 



Hab. Whangaroa Harbour, on rocks, type (Captain Farquhar) ; 

 between Mahia and East Cape, by trawl (Professor Benham). 



2. Chromodoris aureo-marginata, Cheeseman, 1881. Plate 37, 

 fig. 3. 



Chromodoris aureo-manjinata, Chsm., T.X.Z.I., xiii, 1880 (1881), 223 ; Eliot, 

 P. Mai. S., vii, 229, 34(3. 



Body linear-oblong, much depressed, expanded and rounded in 

 front, then contracted, and gradually tapering to a point behind. 

 Colour pellucid white, with a narrow orange line within the mantle- 

 margin on both sides. Mantle quite smooth and even, fairly wide at 

 the sides and amply expanded over the head ; sometimes there are 

 traces of small low tubercles on the back ; it is abbreviated posteriorly, 

 and not nearly concealing the foot, sometimes deeply notched on the 

 right side ; margins thin, even. Rhinophores rather long, linear, 

 tapering a little upwards, with about 20 laminte, retractile within 

 simple-edged and somewhat raised pockets. Branchial plumes 1 to 10, 

 simply pinnate, erect or incurved at the tips, retractile within a common 

 cavity. Foot much longer than the mantle, rather narrow, pointed 

 behind, very thin and flexible, with a simple groove in front. On 

 either side of the mouth is a knob-like tentacle. 



Length 13-38 mm. Length, 12-5 mm. ; breadth, 5-5 mm. (a small 

 specimen, preserved in alcohol). 



The labial armature is rather faint. It is an imperfect ring, com- 

 posed of close-set short mace-like rods, swollen and bent at the tips. 

 The radula consists of 50 rows, three of which are imperfectly developed, 

 containing about 45 teeth on either side of the rhachis, which bears 

 inconspicuous thickenings. The first lateral is broad, and appears 

 trifid, but the prominence on the inner side bears 2-3 denticles. The 

 second lateral is also broad, but lacks this prominence on the inner 

 side. Apart from its greater breadth, it has the same shape as the 

 other teeth namely, 2 large prongs at the apex, .and below them 

 3-6 denticles, which diminish in size downwards. The outermost teeth 

 bear about 4 denticles on the tip. (Eliot.) 



Hab. Auckland Harbour and Waiwera (Cheeseman) ; Narrow 

 Neck Reef, Devonport (H. S.) ; Akaroa Harbour (H. S.). 



Remarks. This form is nearly allied to C. marginata (Pease), and 

 perhaps merely a variety of it. The coloration is very similar and the 

 radula is rather narrow in both species : 50 x 45 + 1 + 45 in C. aureo- 

 marginata, and 54x35+1 + 35 in C. marginala, examined by Bergh. 

 But the similarity in coloration is not complete, and there is a difference 

 in the shape of the teeth: in C. marginata Bergh found them simply 



