54 FOOTE : GEOLOGY OF MADURA AND TINNEVeLLY DISTRICTS. 



To the south o£ the Tambraparni river hardly any traces of the pale 

 Gravels at Mananja- non-ferruginous gravels remain. One very faint 

 P^**^' sprinkling of such gravel was noticed about half 



a mile east of the village of Mananjapatti (Keel Monunjaputty), 14 

 miles south-by-east of Palamcotta. Very little also of the ferruginous 

 conglomerate is seen south of the Tambraparni except in the southern 

 half of the Nanganeri talnq, where numerous patches are to be found 

 scattered over the surface of the gneissic rocks, e.g., along the high road 

 Lateritic conglomerate f^'o^^ Valliur (Vullioor) to Radapuram (Rautha- 

 near Kadapuram. poorum) and the salt-pans (now abandoned) on 



the Vijayapatti (Vissiavethee) creek. Much similar ferruginous conglo- 

 merate is to be seen along a parallel line of country about 3 or 4 miles to 

 the westward. Some of these patches of laterite may be of sub-aerial 

 origin, but it is very difficult and often impossible to distinguish them 

 from the sedimentary rock during a cursory examination, and the form- 

 ation is certainly not one of sufficient importance, either geologically 

 or economically, to justify the expenditure of much time in settling the 

 question in the case of small and obscure patches. 



None of the lateritic deposits met with in Madura or Tinnevelly threw 

 ,, . ^ , ^ any light on the debateable question of the ma- 



Marine or fresh water jo i 



oriffin of the laterite rine or fresh-water origin of the sedimentary 

 stiU unsettled. . ^ 



laterite, as none or the tracts surveyed yielded even 



the faintest trace of any organism. To my mind the marine hypothesis 



still seems to present the smaller number of difficulties, but I will 



not attempt to enter upon any further discussion of the question here. 



In conclusion it may be well to draw attention to the general resem- 



„ . , , , blance of the non-ferruo'inous shingle and g-ravel 



Resemblance between ° o o 



pale gravels and Con- beds of the south to tliose Occurring in the neigh- 

 jeveram gravels. -i i t n 



bourhood of Madras and described by me under 



the name of Conjeveram gravels in the memoir on the geology of Madras 

 published in Volume X of the Memoirs of the Geological Survey of 

 India, — see also Manual. The most marked resemblance to this Con- 

 jeveram gravel is presented by the shingle exposed at the western end of 

 ( 54 ) 



