Chap. VII.] trichinopoly district — trichinopoly group. 109 



away to the Westward, to admit of recognizable traces of it being 

 carried to the existing deposits of the area. The faulting which occurred 

 at the close of the Ootatoor period, must have brought this ridge above 

 the level of the sea ; and accordingly the conglomerates of both the Tri- 

 chinopoly and Arrialoor groups are full of pebbles of felspar, quartz, and 

 the granite itself, and also of the highly foliated hornblende schists, 

 which are associated with the granite, and do not occur elsewhere in the 

 neighbourhood. In the two later groups also we find frequent masses 

 of loose unstratified gravel, composed almost exclusively of granitic 

 debris ; and in some places beds of rolled pebbles, almost without any 

 admixture of finer materials, composed of the quartz of this rock, 

 mixed with gneiss pebbles, and closely resembling in its features of 

 accumulation an ordinary recent shingle-beach. The greater part of the 

 Characters of other Trichinopoly beds, however, consist of fine sands 

 and clays, with infiltrated kunkur, much resem- 

 bling those which constitute some of the Southern Ootatoor beds, and 

 bands of limestone of the different varieties met with in the Ootatoors 

 are also occasionally intercalated, though less common. 



Between Alundanapuram and Garoodamungalum, or rather in the 



country to the East of these places, the beds begin 

 Northern part of group. 



to assume a definite strike parallel to the longitu- 

 dinal axis of the group. Regular bands of shell limestone become inter- 

 calated in the lower beds, and hence to the Northern termination of the 

 group, regularly stratified alternations of sands and sandy clays and 

 shales, with bands of shell limestone, calcareous grit, and conglomerate 

 constitute the whole of the group, with unimportant exceptions. 



The fauna of the Trichinopoly group is, as we might expect from the 



Faima of Trichinopoly peculiarities of its stratification, characterised by 



S^°^V' an abundance of shallow water forms. Many of 



these are already well known from the collections of Messrs. Kaye and 



Cunliffe, described by Professor Forbes, and, as I have remarked in a former 



