ON THE 'manure' GRAVELS OF WEXFORD. 137 



mucli broken for identification of species ; it might be either M. green, 

 landica or M. cornea, both of which Mr. R. A. C. Godwin-Austen, in 

 ' The Natural History of the European Seas,' p. 262, states to occur here. 

 This is, I venture to think, an error on his part. 



Of the existence of the other species in tlie list there can be no doubt, 

 and the question arises, by what routes did they come, and where do 

 similar accumulations occur ? On the latter point Melampus pyramidata 

 is valuable evidence ; its last appearance as a fossil occurring in Eastern 

 England, in the Chillesford beds of Suffolk, in association with Leda 

 oblongoides, Nucula Cobboldia?, Turritella incrassata, Scalaria green- 

 landica, Trophon clathratns, and others in the list just given. 



On the west coast of England it, in company with numerous other 

 shells of southern origin and Pliocene age, occurs in the St. Erth valley 

 in Cornwall, Turritella incrassata being a very abundant form ; and the 

 conclusion arrived at by the writer is that the Wexford scries cannot be- 

 placed earlier than at or about the close of the Pliocene stage of East 

 Britain, such as the Weybourn beds of Norfolk. 



Professor Forbes was the first to suggest that ' there was a communi- 

 cation between the Mediterranean and the North Seas during this period.' 

 Messrs. Dolfuss and Dautzenberg have also pointed out that the Cotentin 

 deposit in North France is but an extension in continuation of the late 

 Miocene seas. 



The deposit at St. Erth' is evidently a further extension in a westerly 

 direction, and a still further prolongation in a line northerly from St. Ertb 

 to the Avest of Carnsore Point would strike the valley between the Wex- 

 ford ridge and the Forth Mountain, and continuing round the inland face 

 of the hills already referred to reach the present coast-line just north 

 of Arklow. 



Such an extension would account for the presence of these southern 

 species in the Wexford area. By what route the northern species arrived 

 will be considered in the final report. 



(ii) Marls and Clays. 



On the survey maps it is said, ' The low lands of this coast and the 

 interior up to a height of between 200 and 300 feet are covered by Pleis- 

 tocene deposits, consisting of marls interstratified with sand and gravel 

 containing arctic and other shells, chalk flint, pebbles of Antrim chalk, 

 jasper, coal, and magnetic iron-sand.' 



This description is not very definite, as the deposits vary much in 

 character and are apparently of difiFerent ages. In Rosslare Bay, near 

 Ballygeary, the lowest bed rests directly upon the base rock, and is a 

 stiff black clay, originating from the black Carboniferous limestone a short 

 distance away, and is only occasionally relieved by a few quartz pebbles, 

 Cambrian rocks, or a limestone pebble or fossil. A bed of sand, more or 

 less intermittent, ranging from thi-ee inches to three feet in thickness, 

 separates this from an overlying very dai'k clay, with a few large stones 

 and occasional seams of gravel. Fossils are present, but are fragmentary 

 and difficult to find in the clay, but are better preserved in the pebble 

 seam.s, from one of which, situated towards the top of the cliff to the west 

 of the pier, the following species were obtained : — 



' On the Pliocene beds of St. Erth, by P. F. Kendall (the late), K. G. Bell, 

 F.G.S., Quart. Journ. Geol. Soc, Lend., 1886, p. 202 et seq. 



