GASTEROPODA NUDIBRANCHIATA. 843 



Flabellina, Cuv. 



The tentacula of the Eolidae, with radiating rectiform branchiae, 

 supported by five or six pedicles on each side; they are closely allied 

 to the Glauci, and in fact to all the Nudibranchiata, whose branchije 

 are situated on the sides of the back(l). 



Tergipes, Cuv. 



The form of the Eolidise, but only two tentacula, with a range of cyl- 

 indrical branchiae on both sides of the back, each of which is termi- 

 nated by a little sucker or cup, and which are used by the animal as 

 feet, to walk on its back. The species known are very small(2). 



BusiRiSj Risso. 



The body oblong, and back convex; two filiform tentacula, and be- 

 hind them, on the nape, two plumiform branchi3e(3). 



Placobranchus, Van Hasselt. 



Two tentacula and as many labial lobes; the whole back, widened 

 by its margin, is covered with numerous radiating striae, which are 

 the branchi^. In its ordinary condition the widened borders of the 

 mantle are turned up, and cross each other to form an envelope for 

 the branchiae, which are thus enclosed, as in a cylindrical case. 

 They are small MoUusca, from the Indian Ocean(4). 



ORDER III. 

 INFEROBRANCHIATA. 

 The Inferobranchiata have nearly the same form and or- 



(1) Dorisaffinis, Gm., Cavol., Polyp. Mar., VII, ,4. 



(2) Limax iergipes, Forsk.. XXVI, ,, or Doris lacinulata, Gm.; Doris macu- 

 lata, Lin. Trans., VII, vii, 34; Doris pennata, Bomme, Act. Fless., I, lii, 3? 



(3) Busiris griseus, Risso, Hist. Nat. Mar., IV, pi. i, f. 6. 



(4) In the species known {Placobranchus Hasselti, Cuv.), the branchial stris are 

 green, and the body a brown-grey sprinkled with little ocelli, Van Hasselt., Bul- 

 let. Univ., Oct., 1824, p. 240. Messrs Quoy and Gaymard found it at the 

 Friendly Islands. 



