Rostanga.] GASTROPODA. 567 



bundles on the top of the other teeth, being apparently set higher up 

 on the sides of the buccal cavity. Their bases are so close together 

 that they seem to be fused, but this is not really the case : each tooth 

 is" separately attached to the basal membrane. (Eliot.) 



Type in the British Museum. 



Hal). New Zealand, exact locality unknown. 



Remarks. The dentition of this species is remarkable, but appears 

 to be much the same as that of R. pulchra, MacFarland, from Cali- 

 fornia. Cheeseman's Doris rubicunda seems also to be a Rostanga, 

 and is perhaps identical with this species, in which case Abraham's 

 name has priority. The type specimen does not look as if it had ever 

 been scarlet, but Cheeseman's statement that D. rubicunda has some- 

 times a darker line down the centre of the back makes the identifica- 

 tion probable, though it is curious that he does not describe the re- 

 markable features of the radula more fully. MacFarland states that 

 R. pulchra loses its scarlet in alcohol ; but, though it is nearly allied to 

 this species, the two are probably distinct specifically. Among other 

 points of difference, it has only 8-11 denticles on the first lateral tooth, 

 whereas R. muscula has about 30. The latter seems to have no regular 

 labial armature, but it is possible that the cuticle of the type specimen 

 has decayed and the plate become decomposed. (Eliot.) 



2. Rostanga rubicunda, Cheeseman, 1881. Plate 37, fig. 7. 



Doris rubicunda, Chsm., T.N.Z.I., xiii, 1880 (1881), 222. Rostanga rubicunda, 

 Chsrn. : Eliot, P. Mai. S., vii, 1907, 328, 340. 



Body oblong, blunt at both ends, sides nearly parallel, back ele- 

 vated. Mantle not much larger than the foot, densely covered with 

 minute, closely packed, narrow, erect tubercles. Colour bright scarlet, 

 sometimes with a darker line down the centre, and with a few scattered 

 blackish specks. Rhinophores clavate, short, stout, completely re- 

 tractile ; lower part cylindrical, whitish ; central part much broader, 

 furnished with about 12 broad laminae that run obliqiiely upwards ; 

 apex a small projecting flat-topped style. The tubercles round the 

 base of the rhin.oph.ores are rather larger than elsewhere, and of a 

 paler colour. Branchice completely retractile, 8 in number, small, 

 erect, oblong, bipinnate. Oral tentacles free, narrow-linear. Head 

 rounded, fleshy. Foot the same colour as the mantle or slightly 

 darker, obtuse, and slightly notched in front, behind pointed and 

 extending beyond the mantle when the animal is crawling. (Cheese- 

 man.) 



Length, 8-25 mm. 



Odontophore broad, of very numerous rows of teeth, central tooth 

 wanting, laterals about 50 on each side, those nearest the centre short 

 and hooked, those on the outside much longer and more slender, 

 strongly arched. (Cheeseman.) 



