SKETCH OF A GENERAL ARRANGEMENT
OF THE
N U D I B R A N C H IA T E MOLLUSCA.
Order—NUDIBRANCHIATA.
Sub-Order—Acanthobranchiata, Ferussac.
Branchiæ on the medio-dorsal line ; skin spiculose.
Earn. 1. Doridida. Cloak large, without marginal appendages; dorsal
tentacles 2, retractile within cavities; oral tentacles 2, various
or wanting .
Fam. 2. P olycerida. Cloak small or obsolete, generally with marginal
appendages; tentacles variable; mouth occasionally provided
with jaws . . . . .
GEN.
r 1. Doris.
2. Chromodoris.
3. Lamellidoris.
4. Hexabranchus.
5. Acanthodoris.
6. Goniodoris.
7. Idalia.
8. Ancula.
9. Polycera.
10. Thecacera.
11. Triopa.
12. Euplocamus.
13. Plocamophorus.
14. Ægirus.
15. Ceratosoma.
Sub-Order—P olybranchiata, Ferussac.
Branchiae arranged along the sides of the body; skin generally without spicula.
Tribe 1. Liver generally central; branchiae laminated.
Section 1. With the branchiae on the under side of the cloak.
Fam. 3. Phyllidiada. Cloak large, spiculose; dorsal tentacles 2, retrac-
tile within cavities in the cloak;. oral tentacles 2 ; anus C
postero-dorsal; mouth without jaws . . )
Fam. 4. Diphyllidiada. Cloak large; dorsal tentacles 2, situated in ^
front of the cloak, with a veil above the head; anus lateral; I
digestive organs with a rudimentary gastro-hepatic system; |
mouth with jaws . . . . J
16. Phyllidia.
17. Fryeria.
18. Diphyllidia.
Section 2. With the branchiæ on the upper side of the cloak. .
GEN.
Fam. 5. Tritoniadæ. Body subquadrilateral; cloak small; veil large;
projecting in front of the head; branchiæ arranged on the
palliai ridge ; anus lateral ; jaws large
Fam. 6. Scyllaida. Body compressed; cloak produced into lateral
lobes, bearing the branchial plumes ; anus latéral ; mouth with > 20. Scyllæa.
jaws . . . )
Tribe 2. Liver diffused ; branchiæ papillose, simple, or branched.
Section 1. With a posterior central gastro-hepatic vessel; reproductive organs with a
single external orifice.
^ 19. Tritonia.
a. With the posterior vessel of-the gastro-hepatic system below the ovary.
Fam. 7. D endronotida. Tentacles 2, dorsal, usually laminated and "| 21. Dendronotus.
retractile within sheaths; branchiae branched or papillose, in a I 22. Bomellia.
single series along the sides of the back; veil small; anus 23. Lomanotus.
lateral; mouth with jaws . . . J 24. Hero.
Fam. 8. T ethida. Body depressed; cloak indistinct; veil very large,
funnel-shaped; tentacles 2, dorsal; branchial plumes alter- >25. Tethys.
nating with papillae; anus latero-dorsal; no jaws . )
Fam. 9. Meltbida. Cloak wanting; tentacles 2, simple, retractile within 'j
sheaths; branchiae clavate, muricated or tuberculated, set in I 26. Melibe.
, single series on each side of the back; anus latero-dorsal; no | 27. Doto.
jaws . . . .
Fam. 10. P roctonotida.. Body depressed; tentacles 4, dorsal pair non-
retractile, without sheaths, oral pair small; branchiae fusiform,
arranged on an obsolete pallial ridge, on each side of the
back, and in front of the head; anus postero-dorsal; mouth
with jaws .
Fam. 11. Glaucida. Body elongated; tentacles 4, linear, simple, nonretractile;
branchiae arranged in a palmate form on extended >- 30. Glaucus.
footstalks; anus lateral; mouth with jaws . • J
28. Proctonotus.
29. Antiopa.
b . With the posterior vessel of the gastro-hepatic system above the ovary.
Fam. 12. Eolidida. Without cloak; tentacles 4, non-retractile, variable;
branchiae simple, papillose or linear; anus lateral; mouth
with jaws .
"31. Calma.
32. Flabellina.
33. Facelina.
34. Coryphella.
35. Favorinus.
36. Phidiana.
37. Eolis.
38. Cuthona.
39. Cavolina.
40. Galvina.
41. Tergipes.
42. Embletonia.
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