270 MR T. J. EVANS ON 



was distributed for identification, the animal went astray, and Sir CHARLES ELTOT, who 

 received the Nudibranchs, comments with surprise on the complete absence of Dorids. 



Dr BRUCE has provided the following notes on the haul in which the animal was 

 included: " Locality, 71 22' S., 16 34' W. Bottom temperature, 31 "9 F. Surface 

 temperature, 29 '9 F. Depth, 1410 fathoms. Bottom, blue mud." The haul included 

 specimens of nearly every group of animals from sponges to fishes. 



It is proposed to name the new species Bathydoris brownii, in honour of Dr R. N. 

 RUDMOSE BROWN, naturalist to the expedition. To him and to Dr BRUCE the author's 

 thanks are due for permission to undertake the investigation of its anatomy. 



The six known species of Bathydoris may be tabulated as follows : 



1. B. abyssorum, Bergh. 2425 fathoms, off New South Wales. " Challenger." 



2. B. ingolfiana, Bergh. 1870 fathoms, in Davis Strait. " Ingolf." 



3. B. hodgsoni, Eliot. 100 fathoms, off Coulman Island. "Discovery." 



4. B. inflata, Eliot. Depth not stated, off Coulman Island. "Discover}/." 



5. B. clavigera, Thiele. Depth not stated, Gauss Station. " Gauss." 



6. B. broivnii, sp. nov. 1410 fathoms, off Coats Land. "Scotia." 



The specimen was preserved in about 5 per cent, formaldehyde, and suffered very 

 little distortion or contraction. The viscera were also in excellent condition for 

 dissection, and even the histological preservation was found to be remarkably good 

 when certain tissues were cut and stained for identification. 



EXTERNAL FEATURES. 



The animal, as preserved, was 75 mm. long, 40 mm. broad, and 35 mm. in height. 

 A thin, flabby foot margin extended about 8 mm. beyond the body all round and 

 was rather bluntly pointed behind, while anteriorly its thickened edge ran transversely 

 across the body behind the head, and had a deep glandular furrow extending into the 

 lateral margin for some distance. The contraction of the foot when the animal was 

 killed probably accounts for the distension of the dorsal integument and the extruded 

 condition of the genital organs, which were forced out to the extent usual among 

 Dorids during copulation. The mouth lies entirely on the ventral aspect, and is 

 surrounded by crinkled lips surmounted by a bulging forehead, which extends laterally 

 into rather long cylindrical oral tentacles. Nearly a third of the length of the ventral 

 surface is occupied by the buccal region, the enormous size of which is a striking 

 feature of the genus. The arched dorsal surface is covered by an integument which is 

 delimited all round the body by a slight fringe at a distance of 4 or 5 mm. from the 

 foot. Laterally this fringe or reduced mantle edge is represented by little more than 

 a linear thickening of the skin. The dorsal integument is thin, transparent, and 

 destitute of spicules, but, as in hodgsoni, inflata, and clavigera, the whole surface seems 

 to have been originally studded with papillae. Those that remain on exposed parts 



(ROY. sou. EDIN. THANS., VOL. L., 11)2.) 



