go .lOtJRkAL OF CONCHOLOGY, VOL. 12, NO. 3, JULY, Igof. 



slightly plicated. In the stomach is. a girdle of about twenty plates, 

 grey and hard. Their outline is roughly half an ellipse but sometimes 

 irregular. In some cases at any rate they are divided by membranous 

 partitions with indented edges. No jaws were found. The anterior 

 portion of the digestive tract was removed and subsequently examined 

 with greater care for traces of these organs but none could be dis- 

 covered. The black colour of the lips and tube was found to be due 

 to the presence of granular pigment, brown where diffuse and black 

 where concentrated. The arrangement of the pigment is dentritic in 

 places and the pigmented parts are not hard. 



I think this animal is the Alelibe pilosa of Pease (i860), and this 

 specific name has priority should it prove to be identical with M. 

 papulosa (de Filippi, 1874), or M. vexlllifera Bergh (1880). The 

 coloration is much as described by Pease and the following points 

 of resemblance are noticeable. (i) The foot of Melibe pilosa is 

 "linear, grooved .... and acute at both ends." (2) The 

 back bears "six pairs of thick tuberculate lobes .... all 

 easily deciduous, contracted at the base, truncate above, convex out- 

 side, and flattened on inner surface." (3) "Everywhere with small 

 soft branched tentacular processes." 



J/"^//<^<? ///6'j'a appears to be distinguishable from Melibe fiinbriata 

 which has (<?) stouter filaments, not thread-like processes; {b) cerata 

 of a different shape and longer; (t) no black pigment in the buccal 

 parts and oesophagus. 



As M. vexillifera (from Enosliima) and M. papulosa (from Yoko- 

 hama) were captured in the same parts of Japanese waters as this 

 specimen, the identity of all three species is highly probable, though 

 it is difficult to demonstrate it from the descriptions. The papillae 

 are certainly not as described by Bergh for M. vexillifera (humiles, 

 vexillo latiori dentato praeditte) but it is possible that they might assume 

 such a shape if contracted in alcohol. Both M. vexillifera and the 

 present species are described from single specimens and it is possible 

 that the shape may vary even in the living animal. 



Tapparone-Canefri stated that his Melibe papulosa had no jaws and 

 I could find none in this specimen. Bergh, however, found them 

 in the specimen which he described as M. papulosa. They are 

 certainly difficult to discover in this genus and possibly there may be 

 some variation even in the same species, that is to say the organs, 

 which are always vestigial, are not developed at all in some specimens. 



Alder and Hancock, Mr. Farran, Mr. Crossland and myself have 

 reported that jaws are absent in AT. fiinbriata. I have, however, 

 recently found them distinctly present in a specimen from Zanzibar. 



At the bottom of the hood of this specimen are a pair of fleshy lips 

 and just below these, at the beginning of the short tube leading to the 



