NUDIBRANCHIATE GASTEROPODA. ,j 



The family comprises the genera Coryphella with lengthened, slender body, and a masticatory 

 edge of the mandibles bearing several rows of denticles; Gonicolis, which is more clumsy with a br< 

 head with strong rhinophores; and the nearly related Chlamylla with its projecting dorsal brim, its 

 scarcely denticulated masticatory edge, its scarcely denticulated lateral teeth, and a developed prostate 

 gland; the genus Himatella, finally is separated from the others by its perfoliated rhinophores. 



Coryphella, Gray. 



R. Bergh, 1. c. 1892. p. 1027 — 1029. 



A series of «species» of this genus have been described, but great part of these, surely, will 

 disappear as being synonymous. 



They belong for the greater part to the more cold and temperate parts of the sea. 



Coryphella sp. (anonyma). 



PI. Y, figs. 14—16. 



In 1S95 two specimens were taken on 66°35' Lat. N., 55 54' Long. W. (station 31) at a depth of 

 88 faths (temp. 16), one 2 cm , the other i"5 cm long; preserved in alcohol they were quite yellowish white. 



In the larger specimen the body was 4 mm high, 7""" broad; the highly contracted tentacles and 

 rhinophores had a length of only 3'5' n "\ the papillae rose to a length of 4'5'" m ; the foot was 4 , 5 m,n broad, 

 of which i-^mm belonged to the footbrim, moreover the corners of the foot projected i-^ mm ; the length 

 of the tail was also i'5 mm . -- In the back of the neck the central nervous system with the black eyes 

 shone through, on the right side of the body the white anterior genital mass did so. 



The form was as usual. The papillae closely set on the lateral parts of the back, were in- 

 distinctly arranged in transverse rows, and these rows, perhaps, were gathered into three chief groups, 

 the rows containing scarcely upwards of 4 — 6 papillae; the papillae were firmly attached, lengthened- 

 conical. The projecting anal papilla was situated under the middle of the length of the dorsal edge, 

 the fine renal pore midway between this and the genital papilla. 



The cerebro-pleural ganglia were angular-oval, with a distinct transverse furrow; the roundish 

 pedal ones were a little larger than the pleural ones, the commissures between them rather short 

 The nerve-cells, especially those of the pleural ganglia, were very large, and rose to a diameter of 

 0-26™™. — The almost sessile eyes had a diameter of o , i2 mra with a large yellowish lens; the otocysts 

 were only a little larger than the eves, with many clear otoconia. 



The bulbus pharyugeus was 3'""' long, by a height of C75 mm , and a breadth of 2 mm ; of the 

 common form, the radula-sheath only slightly projecting. The light yellow mandibles were oi the 

 same length as the bulbus; the hinge-part was not strong; the masticatory process short; the masti- 

 catory edge with 4 — 5 rows of rounded teeth (fig. 14) rising only to a height of o - 009 mm . The second- 

 ary oral cavities were rather wide, hut their opening rather narrow. The tongue oi the common 

 form, the radula colourless. The median tooth-plates were yellowish in the basal part, otherwise 

 tooth-plates were almost colourless. The height of the median teeth on the hindei part oi the tongue 



