COOKE : NOMENCLATURE OF BRITISH NUDIBRANCHIATA. 63 



where, however, no description is given, but only the name. 

 Alder and Hancock described the species in Brit. Nud. 

 Moll., p. 42 ; Fam. i, pi. 7. 

 P. 86. Doris repanda, A. and H. — This species is, I believe, 

 to be identified with Doris ohvelata, O. F. Mliller, as has 

 already been held by Loven and others. As, however, this 

 view does not yet appear to have received acceptance in this 

 country, the question may be examined in detail. Miiller 

 gave the usual brief description in his Prodromus, p. 229, 

 no. 2769 (1776), and followed this up by a more detailed 

 account in the Zoologia Danica, ii, p. 8, tab. xlvii, f. i, 2 

 (178S). The important parts of this account are subjoined, 

 together with Alder and Hancock's description of their 

 repajida ; the figures of both authors should also be compared 

 with the descriptions throughout. 



Body above an inch long [L. i inch. [Miiller's fig. 2, of pi. xlvii measures 



Brit. Conch., v. p. 87], of a pure, waxy, exactly one inch.] 



transparent white. Corpus elongatum subtus glabrum 



Cloak widely expanded, covered with album, supra lamina repanda obtectum; 



small, distant, obtuse and rather incon- et corpus et lamina, aliquantum pellu- 



spicuous opaque white tubercles .... cent. 



An irregular row of opaque white or Lamina supra convexis inaequali- 



sulphur yellow angular spots runs down bus, papillulas simulantibus, ac in sul- 



each side at a short distance from the phureum vergentibus, subtus vero ven- 



margin of the cloak, which is thin and ulis creberrimis non in omnibus aeque 



broad, extending much beyond the foot, conspicuis exornatum est. 

 and marked on the under side with 

 slender white nerve-like lines towards 

 the margin. 



Branchiar small in proportion to the In medio versus postica punctum 

 size of the animal, consisting of five im- mains laminae concolor ; exhoc lobus 

 perfectly tripinnate transparent white confuse serratus, ani ornamentum, pro- 

 plumes ; the three anterior ones ele- truditur. 

 gantly formed and distinct, the posterior 

 deeply divided and irregular, making it 

 difficult to determine their number. 

 They are retractile within a single 

 cavity. In ipso corpore nee os, nee caput diu 



Mouth small, with two flat tentacular detegere potui ; antica demum corporis 



appendages, united above so as to form pars in orbiculum porrigebatur ; hie 



a subquadrangular veil [oral tentacles cajmt medio rima longitudinali seu ore 



flattened and broadly angulated ; Brit. notatum, loboque auriculari utrinque 



Conch., V. 87.] iuxta basin adauctum obtulit. 



The coincidences in these two descriptions are remarkable. Both 

 note the transparency of the body, the wide expansion of the notaeum 

 or "cloak," Miiller actually describing it as repanda, the sulphur- 

 yellow of the tubercles, the remarkable distinctness of the veining 

 underneath the notaeum, and the confused nature of the serrations of 

 the branchial plumes. Alder and Hancock do not state that the 



