234 MR. P. S. ABRAHAM ON THE { Mar. 6, 
3. CERATOSOMA GRACILLIMUM, “Semper,” Bgh. in Semper’s 
‘ Reise im Arch. d. Phil.’ 2te Th. 2te Bd. Heft v. T. 25. p. 8 (1873), 
& Heft x. p. 403 (1876). 
Hab. Philippine sea. 
4. C. caLepontcum, Fischer, Journ. de Conch. sér. 3, tom. xvi. 
p- 92 (1876). 
Hab. New Caledonia. 
5. C. renur, Abraham, Ann. & Mag. Nat. Hist. 4th ser. xviii. 
p. 141, pl. 7. f. 5, 5a, 56 (1876). 
Hab. 2 
6. C. BREVICAUDATUM, id. J. c. p. 142, pl. 7. fig. 6. 
Hab. Australia. 

7, C. osLoncuM, id. Ll. c. p. 143, pl. 7. f. 7, 74, 7b. 
Hab. W. Australia. 
8. C.? weBBil'. 
Polycera webbii, D’Orbigny, Hist. Nat. des iles Canar, ii. “ Moll.” 
p. 41, pl. 4. f. 8-10 (1837). 
Goniodoris webbii, Gray ; Doriprismatica webbii, H. & A. Ad. 
Hab. Canary Isles. 
Gen. TREVELYANA, Kelaart, 1858. 
Gymnodoris, Stimpson’, 1855. Stenodoris, Pease’, 1866. 
Body limaciform, rather swollen or raised on the central region. 
Mantle obsolete. No appendages. Rhinophores laminate and retrac- 
tile. Branchie pinnate, non-retractile, placed round the anus almost 
on the centre of the back. Mouth without oral tentacles or veil, and 
without collar or jaws. Odontophore broad, bearing simple spines. 
1. T. ceytonica, Kel. Amn. & Mag. Nat. Hist. 3rd ser. i. p. 257, 
pl. 108. f. 1, 2 (1858). 
T. zeylanica, id. 
Hab. Ceylon. 
1 This may prove to be the type of a new genus; from D’Orbigny’s deserip- 
tion it would seem to be intermediate in character between Ceratosoma and Poly- 
cera. 
2 Stimpson’s diagnosis is :—‘‘Limaciform, smooth. Similar to Polycera, but 
different in wanting branchial appendages and aveil. Branchix likewise simple.” 
Tt seems to me that there is little doubt that this is synonymous with Kelaart’s 
genus. The name Trevelyana, however; has been generally employed, although 
enunciated three years subsequently to Gymnodoris; and, moreover, we cannot 
be quite sure of their identity until Stimpson’s specimens be properly examined 
* Mr. Pease’s Stenodoris does not appear to differ essentially from Kelaart’s 
genus. He states that “the body is deeply incised on either side, a short dis- 
tance behind the dorsal tentacles,” and that the branchie are “ subretractile.” 
