36 



NTJDIBRANCHIATE GASTEROPODA. 



Hitherto the genus only comprised the species found by Sars and examined by me. The 

 Ingolf expedition has brought home two specimens of Gonieolis, mutually different, and one of them 

 especially so deviating from the typical species, that I have thought it better, at least for the present, 

 not to identify these new individuals with the typical species. 



i. Gon. typica, M. Sars. 

 R. Bergh, 1. c. 1885. p. 14—18. Taf. Ill, Fig. 1—26. 



This species seems to be marked off from the two others by a different form of the man- 

 dibles, by a stronger denticulation of the lateral teeth (and perhaps by the want of a specially 

 developed prostate gland). 



2. Gon. intermedia, Bgh. n. sp. 

 PL IV, figs. 16—17. 



Together with the following species one individual of the present species was taken on June 

 n ,h , at 930 a. m. on 66-43' Lat. N., 55° 57' Long. W. with the trawl from a depth of 88 faths (temp. 

 2 C 6— 2 |. 



The specimen that was rather well preserved in alcohol, was of a whitish colour; its length 

 was 2'7 cm , the other measures relatively as in the following species. 



The form was as in the typical species, the dorsal lateral edges more projecting than in the 

 following species; the corners and the fore edge of the foot distinctly projecting, more so than in 

 both the other species; the flaccid, dorsal papillae, many of which had fallen off, rose to a length of 

 6 mm ; the genital openings were quite as in the typical species, and so was the anal papilla. 



The central nervous system together with eyes and otocysts were as in the species de- 

 scribed below. 



The bulbus pharyngeus was to a remarkable degree like that in Chlamylla borealis 1 ), and 

 was likewise hollowed in the hinder part of the upper surface; it was 4"" 11 broad by a length and 

 height of 3""". The light yellow mandibles had the same form as in the following species; only 

 the keel in front on the outside was a little slighter; the masticatory process and the masticatory 

 edge were quite as described below. The tongue was quite as in the following species; in the co- 

 lourless radula 8 series of teeth were seen, and as many in the short radula sheath, which was directed 

 backward; thus the total number of series was 16, of which the two hindmost ones were not yet 

 quite developed. The tooth-plates were almost quite colourless; the breadth of the median teeth rose 

 to o - 2o'" m- by a height of o*io mm , and a length of o*35 mm ; the length of the lateral teeth rose to o - 20 mni . 

 The form of the median tooth-plates (figs. 16 a, 17 a) was between the form of those in the preceding 

 ies and those in the following one, though nearer to the latter; on each side of the rather short 

 point 12 — 15 rather strong denticles were seen. The lateral tooth-plates (figs. 15b, 17b) were shorter 

 and more clumsy than in both the other species, and without denticulation. 



■) Comp. R. Bergh, die Nudibranchien ... des Willem Barents . 1. c. p. II. Taf. I, Fig. II. 



