EXPLANATION OF PLATKS 43. 44. 63 



Plate 43. V. I. pp. 358, 359. 



Fig. 1. Fragment of Nautilus sypho, in the collection of 

 W. I. Broderip, Esq. from the Miocene division of 

 the Tertiary formations at Dax, near Bourdeaux. 

 The accidental fractures of this fossil afford an in- 

 structive display of the disposition of the transverse 

 Plates and Siphuncle. (Original.) 



Fig. 2. Another fractured shell of the same species from 

 Dax, in the collection of Mrs. Buckland, shew^ing 

 at «i, «2, a^, the disposition of the lateral lobes. 

 See V. I. p. 359, Note. (Original.) 



Fig. 3. Cast of the interior of Nautilus Ziczac, in the 

 collection of Mr. James Sowerby, shewing the dis- 

 position of the lateral lobes. (See V. I. pp. 359, 

 360. (Original.) 



Fig. 4. Cast of a single chamber of Nautilus Ziczac, in 

 the collection of Mr. J. Sovi^erby, shewing the dis- 

 position of the ventral and dorsal Lobes and Si- 

 phuncle. See V. I. p. 359, Note. (Original.) 



Plate 44. V. I. p. 361, et seq. 



Fig. 1. Molluscous animal inclosing the Spirula Peronii. 

 See V. I. p. 362.* (Blainville.) 



Fig. 2. Section of a Spirula (Nat. size), shewing its trans- 

 verse Plates and siphuncular sheath. (Original.) 



* M. Robert has recently discovered between the Canaries and 

 Cape Blanc, several imperfect bodies of a small species of mollus- 

 cous animal, each inclosing a Spirula. 



In all these the position of the shell is not at the posterior extre- 

 mity, as in the figure of the specimen found by Peron, but in the 

 back, parallel to the axis of the body, like the shell of the Sepio- 

 staire, or internal shell of the common Sepia. This position agrees 

 with that of tlie animal figured by Blainville, if we suppose the 

 caudal portion of the latter to have been lost. 



On each side of the body are two expansions that act like Fins, 

 as in the Sepiole. Beneath the neck is the aperture of the Funnel. 



