SL'TEi; : XLW GENUS AxND SJ'L'CIES OF PIIEXACuilELlClUAE. (Jo 



divided, with slight transverse rugae, separated from the foot by a double 

 pedal line. Genital orifice behind the right tentacles ; pulmonary orifice 

 on the right anterior side of the mantle, ending in a short distal slit ; anal 

 orifice on the right side just below the middle of the visceral hump. Tail 

 rounded, with a caudal pore. 



Total length G, height :}. height of neck l.T.j millim. 



Visceral hump : length 4.5, height 2, breadth -J.. j millim. 



Breadth of sole 1.5 millim. 



Shell (Fig. o) auriform, yellowish-horny, flexible, membranaceous, 

 transparent, with a notch on the right posterior side ; one whorl only, 

 with microscopical distant lines of growth. 



Length 2.75, breadth l.(j millim. 



Jaw (Fig. 4) arcuate, delicate, composed of 15 very thin vertical 

 laminae, all of which are separated from one another. 



Eadula (Fig. 5) elongated tongue-shaped, consisting of about 150 

 straight transverse rows of teeth, the formula being lo-l-l-7-\3. The 

 last nuirginal tooth is a minute plate with a rudimentary denticle ; in the 

 two following teeth the denticles still coalesce, but show beginning division. 

 The l)ase of attachment in most of the marginals is much liroader than 

 high. On the 17th tooth the division into distinct teeth begins; the 

 ectocone is always smallest, sometimes bidentate, the mesocone is the 

 stoutest, and the entocone is more slender, and slightly directed towards 

 the centre of the radula. A few quadrate transition teeth occur between 

 the marginal and lateral teeth, on which the ectocone is minute, the 

 mesocone large, reaching to the posterior margin of the base, and the 

 entocone about twice the size of the ectocone. The laterals have a square 

 base, higher than broad, and are tricuspid. The mesodont reaches a little 

 beyond the posterior margin of the base, the side-cusps are short and with 

 minute cutting points. The central tooth is exactly like the mesial 

 laterals. 



On dissecting the minute aninud, 1 found it to be in a ratlicr bad 

 c()ndition for the purpose, but 1 fully sutistied myself that it was inunature. 

 1 hope that further search for this slug will j)rovide adult specimens, when 

 the anatomy can be properly worked out. 



Hub. — Auckland Islands, where it was found Ijy Lady Constance 

 Knox, who handed it over to the Hon. H. C. Butler, and by wluna it was 

 given to Capt. F. W. Hutton. The latter, with his usual kindness and 

 liberality, kindly sent me the unique specimen for description, for which 

 my best thanks are due to him. 



The genus is named, by kind permission, in liun(jur of his Excellency 

 the Earl of Ranfurly, K.G.M.G., etc.. Governor of New Zealand, and the 

 species in honour of his Excellency's daughter. Lady Constance Knox. 



According to the facts Ijrought forwuixl, there can be no douljt about 

 the systematic position of this slug : the presence of a caudal p(jre, the 



