ELIOT: NUDIBRANCHS OF FALKLAND ISLANDS. 361 



I think the genus Cahjcidoris had better be maintained, unless it can 

 be shown that the peculiar branchial cavity is not a natural and 

 permanent arrangement. It differs from Acanthodoris in the presence 

 of this cavity, in having numerous simply pinnate branchiae, and no 

 denticles on the first lateral tooth. It is thus in some ways inter- 

 mediate between Acanthodoris and Adalaria. 



EXPLANATION OF PLATE XXVIII. 



Fig. 1. — AUoiodoris lamigmata : a, labial armature ; h, a single rod from the same. 

 ,, 2. — AUoiodoris Innuginafa: radula : «, two first laterals; b, second lateral; 



c, a tooth from the inner part (3-15) of the half row ; d, a tooth nearer 



the end of the row. 

 ,, 3. — Rostanga muscula: radula: a, first lateral; h, second to eighth laterals; 



e, nintif to thirty-sixth laterals; d, thirty-seventh to eighty-second 



laterals. 

 ,, 4. — Cratena Valentini: a tooth. 

 ,, ^.—Cratena Valentini : li\'ing animal. 



,, 6. — Galvina Falklandica: a row of the radula : «, median ; i, lateral teeth. 

 ,, 7. — Coryphella Falklandica : a row of the radula : a, median ; h, lateral teeth. 

 ,, 8. — Acanthodoris Falklandica: a, first lateral; b, second lateral; c, thii'd 



lateral ; d, fourth and fifth laterals ; e, sixth and seventh laterals. 

 ,, 9. — Cahjcidoris Gihithcri: «, first lateral ; i, second ; c, third ; </, fourth. 



