234 Further Observations on the 



The ground in this neighbourhood is naturally strong; 

 in order to clear it for cultivation, the villagers have thrown 

 these stones into heaps, or have arranged them in lines, so as 

 to form the boundary of their fields. The stones so carelessly 

 thrown aside are sometimes petrified Nautili, or they contain 

 in their surface portions of Baculites, of Ostreas, or even of 

 Ammonites, disclosing interesting sections of their chambers. 

 In fact, there is not one of these heaps that does not furnish 

 a perfect study for the geologist; as it has been recently 

 discovered by Mr. Cunliffe 3 that when fractured the stones 

 composing them almost all contain beautiful portions of Ba- 

 culites, entire Ammonites, and a great variety of shells which 

 I am unable to name. The fracture of course sometimes 

 destroys the shell ; but occasionally they are extricated with- 

 out much damage, in which case they are found to preserve 

 a wonderful degree of freshness. The beautiful Ammonite, 

 figured in drawing * * * was obtained in this manner 

 from a mass of the hard limestone ; and it may be as well to 

 observe in this place, that however hard the stone may now 

 be, (and it is sometimes nearly as hard as granite,) it must, 

 when these shells were deposited in it, have been in a per- 

 fectly soft and almost fluid state, for it retains the sharpest 

 and most minute impressions of the sculpture on the fossils 

 which it encloses. 



A good number of Echini have been found at different 

 times, scattered pretty generally over the surface of the soil ; 

 but they are usually too imperfect to delineate correctly. 

 They are I think of only two species, that figured in Plate II. 

 Fig. 2, of the Madras Journal, and that figured in of these 

 drawings. 



The large bivalve shell described in Plate III. Fig. 3, Ma- 

 dras Journal, is also a very characteristic fossil, and we 

 collected a great number of stony masses, (I presume wood,) 

 bored by the Teredo, very similar to that noticed in my 

 former paper as having been obtained from Trichinopoly. 



