356 NOTES ON ROMK BRITISH NI'DinRANCHS. 



orifices (PI. xil., Fig. 18. e.) which appear to be cnidocysts. Tiiey consist of 

 a fairly broad tube, which is narrowed by u constriction when it reaches 

 the integuments and forms outside the constriction a cup-shaped aper- 

 ture. There are traces of similar openings on the anterior margin of 

 the foot ; but it is unusual to find cnidocysts in this position, and the 

 structure of the organ is not clear. Abundant mucous glands are 

 scattered over the whole surface of the body, and the mucus can be 

 seen under the microscope in the act of exuding. 



The hermaphrodite gland (PI. xii., Fig. 12. 1, n.) is large and fills all the 

 posterior part of the body cavity with large yellowish packets. The 

 anterior genital mass is also well developed, but hardened and not well 

 preserved. No trace of armature was found, and the spermatotheca 

 appeared to be surrounded by the albumen gland. 



DOTO, OKEN. 



A considerable number of species have been referred to this genus, 

 but it is greatly in need of a revision based on a study of a large series 

 of living animals. The internal characters offer few points of difference, 

 and the external characters, such as coloration and the shape of the 

 rhinophore sheaths, are somewhat variable, and liable to be either dis- 

 torted or obliterated in preserved specimens. Bergh, in his System cler 

 Nudib. Gast., registers sixteen species, described chiefly by Alder and 

 Hancock, Hesse, and Trinchese. Of these it would appear that IK 

 arhuscida, Agassiz, and D. mmutf, Forbes, are jnere names. J), anstralis, 

 Angas, is perhaps a Melihc and not a Doto at all, and the later D. ocelli- 

 fcra of Simroth {Die Gasteropoclen dcr Plankton Expedition, 1895, 

 pp. 168-70) is of very doubtful affinities. The forms which probably 

 Ijelong to the genus may be enumerated as follows : — 



1. Doto coronata (Gm.). 10. D. cinerea, Trin. 



2. Z). /o?-mos«, Verrill. 11. D. pinnatijida Qlig.). 



3. D. cusjndata, A. & H. = D. splendida, Trin. 



4. D. fragilis (Forbes). 12. D. paulince, Trin. 



5. D. crassicornis, M. Sars. 13. D. indica, Bergh. 



6. D. costcc, Trin. 14. D. africana, Eliot. 



7. D. cornalicc, Trin. 15. D. Jioridicola, Simroth. 



8. D. rosea, Trin. perhaps = Z'o^t/Zr/ (.?)j7?/^»(a'«, Bergh. 



9. D. aurea, Trin. 16. D. (inmdigera, Bergh. 



DOTO PINNA'I'IKIDA (MoNT.), VAU. I'AI'ILLIFKKA. 



Tliree specimens from i'lymoutii, nearly a centimetre long. Tlie 

 coloration, cerata, etc., seem typical of the species as described by Alder 

 and Hancock, but there are numerous papillae on the back, each with 



