NOTES ON SOME BRITISH NUDIBRANCHS. 335 



Candiella can be maintained {vide Eliot, "On the Nudibrauchiata of the 

 Scottish National Antarctic Expedition," Trans. Roy. Soc. Bdinb., 

 vol. xli. part iii. p. 523, 1905). 



17. T. alba, A. & H. 



18. 2'. exsulans, B. 



19. T. incerta, B. 



20. T. gi(jantea, B. 



21. T. (Candiella) australis, B. 



22. T. (Cand.) ingolfiana, B. 



23. T. (Cand.) villa/ranca, Vayssiere. 



24. T. ajypendiculata, Eliot. 

 (?= jT. chaUengeriana, var.) 



25. T. olivacea, B. 



26. T. irrorata, B. 



TRITONIA ALBA, A. & H. 



(Monoijr. of the British Nudib. MoUusca, part vii. p. 48, and 



Appendix, p. vi.) 



Specimens of this form were found by Alder and Hancock at Culler- 

 coats, near Newcastle, and described by them as having considerable 

 external resemblance to young individuals of T. /lojnbcrgii, but as 

 diftering in dentition from all known Tritonias, inasmuch as the lateral 

 teeth were denticulate or branched. Bergh (i¥al. Unt. in Semper s 

 Reisen, Heft xv. pp. 734 and 736) rejects the species as doubtful, and 

 thinks tiiat the denticles were merely an illusion of the microscope. 

 An examination of the original specimens preserved in the Hancock 

 Museum at Newcastle-on-Tyne has shown me, however, that this is not 

 the case, and that the teeth are really denticulate. 



The two specimens are respectively 7 and 6 mm. long, and 2*8 

 and 2"2 mm. broad. One is dark brown, the other yellowish. The 

 hard buccal parts are fortunately well preserved, otherwise few 

 characters either external or internal can be established, which is 

 hardly surprising, as the specimen must be at least fifty years old. 

 There is no reason, however, to doubt the accuracy of Alder and 

 Hancock's descriptions. The dorsal margin is large, and seems to have 

 borne in the one specimen six, in the other eight branchi;e of various 

 sizes. No trace of stomach plates was found. 



The jaws are yellow, rather long and narrow, and bear near the edge 

 about four rows of small prominences resembling a mosaic. The radula 

 is very transparent, and consists of twenty-five rows, which appear to 

 contain thirty-six teeth on each side of the rhachis when complete. 

 The rhachidian tooth (PI. XI., Fig. 1. a.) is tricuspid, and hollowed out 



