368 SIE C. ELIOT OK NUDIBRANCHS [DeC. 1, 



10. Thordisa stellata, sp. n. 

 One specimen from Oliuaka. 



The living animal was soft, but yet distinctly harsh to the 

 touch. The colour is a yellowish grey with small sandy patches 

 and also dull chocolate blotches, the latter at the mantle-edge 

 and round the visceral mass. The underside is of a greyish white, 

 with pronounced chocolate blotches round the foot, and a much 

 fainter ring of the same halfway to the mantle-edge. 



The preserved specimen, which is much bent, is 2-8 centimetres 

 bi-oad, and would be at least 3-5 centimetres long if straightened 

 out. The texture is rather leathery, but the back is covered with 

 small soft papillae of various sizes and colours, and all simple. 

 The I'hinophore-openings are slightly raised, closed, and apparently 

 crenulate. The branchial pocket is slightly raised, stellate, and 

 entirely closed by six lobes. The branchife are yellow, tripinnate, 

 five or six in number according as one much smaller than the 

 others is reckoned separately or as an appendage. The rhachis 

 is very thick and broad. The foot is grooved and notched in 

 front. The tentacles are close together above the mouth a.nd 

 somewhat flattened. No labial armature could be found. The 

 radula consists of 36 rows, each containing about 70 hamate teeth 

 of the ordinary type. The innermost are smaller and the outer- 

 most less distinctly formed, but neither rudimentary nor denti- 

 culate. ISTo genital armatui'e was discoverable. 



This specimen appears referable to Thordisa and bears a strong 

 resemblance to 1\ viltosci, but diffeis in the more leathery 

 consistency, the stellate branchial opening, and the outermost 

 teeth of the radula, 



11. Thordisa crosslandi, sp. n. (Plate XXXII. fig. 3 & 

 Plate XXXIII. figs. 4-8.) 



Many specimens of this form were captured at Chuaka, on the 

 East Coast of Zanzibar, in 1901-02. 



The animals are large, the measurements of a fine alcoholic 

 specimen being, length 12-5 centimetres, breadth 9*1, height 2*5, 

 The shape is therefore flat and oval. The coloration is in 

 its general efiect inconspicuous. The upper surface is sandy 

 with blotches of brown irregularly bordered with black. The 

 tinder surface (PI. XXXIII. fig. 3) is whitish with numerous 

 brownish spots and a brownish border. But when the upper 

 surface is carefully examined it presents a great variety of shades 

 of light and dark brown which cannot be easily described or 

 depicted. The back is covered with thick-set pointed papillae, some 

 of which are developed into distinct filaments at their extremities. 

 The general texture is soft. The openings for the rhinophores and 

 branchiae are slightly raised, and may be described as tuberculMe 

 since they open among tubercles, but they do not appear to be 

 provided with special tubercles. The branchial pocket is an 

 irregular oval and not stellate or crenulate. The branchiae 

 (PI. XXXIII. fig. 5) are six in number and tripinnate. The 



