786 CLASS xui. 



received by us in the first edition of this Handbook, u. bl. 89. We 

 see that in this we have been anticipated by GRAY and REEVE. 



Umbrella LAM. (Gastroplax BLAINV.). 



Pleurobranchus Cuv. Body with flat abdomen, a furrow be- 

 tween the mantle and abdomen receiving the branchiae on the right 

 side. Mantle covering the whole of back. Velum in front of 

 mouth acuminate on each side. Two tubular tentacles fissured by 

 an external furrow. Vent behind branchia in right side. Shell 

 dorsal, contained in mantle, horny or calcareous. 



Corap. on this genus CUVIEB Ann. du Mus. v. p. 266 and foil. PI. vm. 

 Mollusq., M6m. VIII. 



Sp. Pleurobr. Peronii Cuv., 1. 1. figs, i, 2, R. Ani., ed. ill., Moll. PI. 32, 

 fig. i; from the Indian Sea; Pleurobr. ForsTcalii LEUCK., FORSK. Icon. 

 Rer. natural. Tab. 28, fig. A, Lepus marinus RUEPPELL, Atlas 1. 1. Tab. 5, 

 fig. 2 ; in the Bed Sea ; Pleur. testudinarius CANTR., Pleur. Forskalii 

 DELLE CHIAJE, Memorie, PI. 41, fig. n; from the Mediter. &c. Comp. 

 CANTRAINE Malac. med. pp. 8790. 



Pleurobranchcea MECK., Pleurobranchidium BLAINV. Four ten- 

 taculiform lacinise, not retractile. Vent above branchia in the 

 right side. Shell none. Mantle shorter than body. 



Sp. Pleurobranchcea MecMii Cuv., DELLE CHIAJE Memorie, PI. 40, fig. n, 

 CANTRAINE 1. 1. PI. in. fig. 3 ; from the Mediterr. Sea. Comp. S. F. LEUE 

 Diss. de Pleurobranchcea. Halse, 1813, C. fig. 



Aplysia L., GMEL. (Laplysia L., typogr. error, LAM.). Body 

 oblong, limaciform, mostly margined by a broad velum reflected 

 over the back. Two contractile tentacles, conical, sulcated, in the 

 upper part of head ; two productions of the velum surrounding the 

 mouth, forming as it were a second pair of inferior tentacles. Eyes 

 sessile in front of base of superior tentacles. Branchise dorsal, 

 covered by a production of mantle, with an operculum including a 

 flat membranoso-corneous or calcareous shell. 



Comp. SANDER RANG Hist. not. des Aplysies. Paris, 1828, fol. 



Doldbella LAM. Operculum of branchiae towards the posterior 

 part of back, including a calcareous shell. Body mostly truncated 

 posteriorly with an orbicular declining area. 



Sp. Aplysia Rumphii RANG, Dolabella Rumphii Cuv., RUMPH. Amb. Rari' 

 teitk. Tab. x. fig. 5 (Tab. XL. fig. N the shell) ; Cuv. Ann. du Mus. v. p. 

 437 and foil., PI. 39, figs, i 4, Moll., Mem. 12, RANG 1. 1. PI. i. 



