96 SIR C. ELIOT ON NUDIBRANCHS [May 17, 



bears eleven pairs of branchiae, the main axis of which is bifid and 

 the secondary axis bifid again. The first pair of branchife are set 

 at the side of the rhinophores, which appear not to be on the 

 dorsal margin, but this arrangement may Le due to the contraction 

 of the anterior part of the animal. The velum bears eleven simple 

 processes of irregular length ; the outermost are tentacular and 

 grooved as usual. 



The jaws bear a single row of very large, bent, almost hamate 

 denticles with slight indications of a second i-ow. The radula con- 

 sists of 36 rows, with a maximum formula of 274-1-1. 1 + 27, but 

 in most rows it is only about 15 + 1.1.1 + 15. The central tooth 

 is broad, and, as in M. ramosa, seems to bear five cusps. The 

 stomach is provided with the usual girdle of about 100 triangular 

 plates, all of much the same size. 



This form appears referable with tolerable cei'tainty to M. 

 arborescens B. 



Marionia ramosa, sp. n. 



One specimen dredged in 5 fathoms, north of Kokotoni, 

 Zanzibar. 



The notes on the living animal are as follows : — " Colour cocoa- 

 like. Two rows of big branched processes which are greenish in 

 their finer divisions. The rhinophoi-es and processes of the velum 

 very long. The neck part is long and the whole creature has the 

 shape of Limax. Length aboiit 2| inches." 



The preserved specimen is of a uniform light yellowish green, 

 much bent, but about 27 millimetres long if stretched out. The 

 back is only 8 mm. across, but the whole animal looks much 

 ]:)roader on account of the large branchia?. These are thirteen in 

 number, set on the somewhat projecting dorsal margin. The first 

 are a little behind the rhinophoi'es and the last at the end of the 

 tail. None are rudimentary, and the longest are 1 1 mm. long and 

 almost ribbon-like. The largest tufts consist of three main stems, 

 each of which is trifid again. The velum is ample and bears, in 

 addition to two tentacles of the visual grooved shape, twelve simple 

 digitate processes. The largest are 2 mm. long; the four in the 

 centre are much smaller than the othei'S. The sides and back are 

 tuberculate. The rhinophore sheaths are 5"5 mm. high, with 

 simple but ample and spreading margins. The club is surrounded 

 by five plumes, once or twice pinnate. 



The jaws are not very strong, and, except that the cutting-edge 

 is yellow, colourless. Both bear about thirty large pyramidal 

 denticles, at the base of each of which is a small accessory denticle. 

 In parts there are traces of a second line, which might be 

 regarded as mere ridges on the first line of denticles, but which 

 in seven or eight cases seem to be independent formations. The 

 ti-ansparent i-adula consists of 45 rows, containing at most 29 

 laterals, so that the formula is 45 X 29+ 1.1.1 -}- 29 as a maximum. 

 The central tooth is much as in Bergh's plates of Ilarionia 

 arhorescens (S. R. Heft xvii. pi. Ixxxviii. fig. 34), and, as 

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