EXPLANATION OF PLATE 44'. 67 



Fig. 1. Imaginary restoration of Belemnosepia, shewing 

 the probable place of its Ink-bag, and of the internal 

 shell or Belemnite. The three component parts of 

 this Belemnite are represented as if longitudinally- 

 bisected : the place assigned to this Ink-bag is 

 nearly the same as in the recent Loligo. (Original.) 



Fig. 2. Sepia officinalis, shewing the position of the 

 internal shell or sheath (Sepiostaire) within the 

 dorsal portion of its sac. Its apex (a,) and cal- 

 careous dorsal plates (^,) correspond with the apex 

 calcareous conical sheath of a Belemnite. 



Fig. 3. Sepia officinalis, laid open along the ventral 

 portion of its Sac, to shew the position of its Ink- 

 bag. (Original.) 



Figs. 3. a, 3. b. 3. c, Rhyncholites, found in contact with 

 Belemnites in the Lias at Lyme Regis, Nat. size. 

 (Original.) 



Fig. 3. d. Beak of a small Testudo from Chalk, in the 

 collection of Mr. Mantell, shewing a fibro-cancel- 

 lated bony structure, very different from the com- 

 pact shelly condition of the Rhyncholite, for which 

 it may from its size and shape be mistaken, (Ori- 

 ginal.) 



Fig. 4. Ventral surface of a Sepiostaire ; the elongated 

 shallow cone, or cup, {e. e. e. e .) is composed of 

 very thin calcareous plates, alternating with horny 

 membranes, which are expanded outwards to form 

 the thin margin of the cone. This irregular cone 

 or shell represents the hollow cone at the larger 

 extremity of the Belemnite, (Fig. 7. b. b'. e. e\ e'\) 

 which includes its Alveolus {b. b',) and Ink-bag (c). 

 Within this shallow sub-conical shell of the Sepio- 

 staire is contained its alveolus, or calcareous cham- 

 bered portion, (Fig. 4. b.) which represents the 



