388 Geological Society. 



in diameter ; some few being larger, others much smaller : — their 

 colour is dark gray ; their substance, like indurated clay, of a com- 

 pact earthy texture ; and their chemical analysis approaches to that 

 of album graecum. Undigested bones and scales of fishes occur abun- 

 dantly in these fajcal masses. The scales are referable to the Dapedium 

 politum, and other fish that occur in the lias ; the bones are those 

 of fish, and also of small Ichthyosauri. The interior of these bezoars 

 is arranged in spiral folds ; their exterior also bears impressions re- 

 ceived from the convolutions of the intestines of the living animals. 

 In many of the entire skeletons of young Ichthyosauri, the bezoars 

 are seen within the ribs and near the pelvis : these must probably 

 have been included within the animal's body at the moment of his 

 death. The author found, three years ago, a similar ball of fsecal 

 matter, in the collection of Mr. Man tell, from the strata of Tilgate 

 Forest, which abound in bones of Ichthyosauri and other large reptiles ; 

 and he conjectures that these bezoars exist wherever the remains of 

 Plesiosauri are abundant. 



3. — Fossil Sepia. — An indurated black animal substance, like that 

 in the ink-bag of the cuttle-fish, occurs in the lias at Lyme Regis ; 

 and a drawing made with this fossil pigment, three years ago, was 

 pronounced by an eminent artist to have been tinted with Sepia. It 

 is nearly of the colour and consistence of jet, and very fragile, with 

 a bright splintery fracture ; its powder is brown, like that of the 

 painter's Sepia ; it occurs in single masses, nearly of the shape and 

 size of a small gall-bladder, broadest at the base and gradually con- 

 tracted towards the neck ; these are always surrounded by a thin 

 nacreous case, brilliant as the most vivid Lumachella ; the nacre seems 

 to have formed the lining of a fibrous thin shelly substance, which 

 together with this nacreous lining was prolonged into a hollow cone 

 like that of a belemnite, beyond the neck of the ink-bag ; close to 

 the base of the ink-bag tiiere is a series of circular transverse plates 

 and narrow chambers, resembling the chambered alveolus within the 

 cone of a belemnite ; but beyond the apex of this alveolus, no spa- 

 those body has been found. 



The author infers, that the animal from which these fossil ink-bags 

 are derived, was some unknown cephalopode, nearly allied in its in- 

 ternal structure to the inhabitant of the belemnite j the circular form 

 of the septa showing that they cannot be referred to the molluscous 

 inhabitant of any nautilus or Cornu-ammonis. 



Feb. 6th. — A paper was read " On the Oolitic District of Bath," 

 by William Lonsdale, Esq., of Bath-Easton. 



The tract described in this paper comprehends a space included 

 between the lines passing, — on the north, from Wycke north-west of 

 Bath, through Marshfield, Kingston-St. Michael, and Lynham, to the 

 Chalk-downs north of Calne and Cherhill ; and on the south and 

 south-east, — from the south of Hadstock, through FromeandWestbury 

 to Devizes. The author refers to the works of Mr. Smith, and of 

 Me.ssrs. Conybeare, De la Beche, and Phillips, as the principal pub- 

 lished authorities on the district : and states his obligations for much 

 valuable information to the Rev. B. Richardson of Farleigh, near Bath. 



The 



