I 



Vol. 57.] PHYSICAL DEVEtOPMElfT 01? ANGIJILLA, ETC. 527 



of mountains and valleys produced by atmospheric erosion. No 

 fossils are contained in these rocks, and their relationship is such 

 as not to establish their age. From their texture and deformation 

 it is suggested that they represent the lower beds of Tintamarre. 



The sea-cliffs along the north-western shore of Anguilla afford 

 opportunities for studying the limestone-formations. The direction 

 of the coast-line often nearly coincides with the strike of the beds, 

 which thus appear horizontal, when in fact they may dip at 

 considerable angles into the island-mass. Between Eoad Bay and 

 the landing to the east, of it there is one section of brecciated 

 limestones cemented by oxide of iron. These beds rise to a 

 height of 30 or 40 feet ; they contain fossils, but in a poor 

 state of preservation. At other points, a marly limestone, inter- 

 bedded with compact layers, rests upon a blue clay (scarcely above 

 wave-action) and rises to a height of about 50 feet. This is 

 succeeded by a more massive limestone from 40 to 50 feet thick, 

 which causes the bluffs to retain their bold features. Overlying 

 it is another marly deposit, of a yellowish colour, which has 

 probably an equal thickness. The variability of the longitudinal 

 exposures along the coast arises from extensive slippings of the 

 higher strata (a fact which is often concealed) and from uncon- 

 formity, as well as from the windings of the coast bringing to view 

 different portions of the formations. In a cove north-east of the 

 Crocus Bay landing, where the heavier limestone succeeds the 

 marl, the strata dip 40° north-eastward (an exceptionally high 

 disturbance). These are unconformably succeeded by another 

 white limestone of compact texture, lying in horizontal beds. The 

 two distinct formations, composed of the same materials, are not 

 physically distinguishable where the unconformity is not apparent. 

 Accordingly, fossils collected from beds whose relationship is not 

 shown are likely to give rise to confusion of faunas. Fuller 

 information may be derived from the corals and echinoderms, 

 these being in a better state of preservation than the molluscs, which 

 occur as casts. 



Among the fossils previously obtained by Mr. Cleve, he mentions 

 several genera of molluscs. He found Natica jyhasianelloides^ 

 d'Orb., a form widely distributed in the Miocene of the West 

 Indies, N. canrena, Linn., and the tubes of a Teredo which occurs 

 in Puerto Kico, as also several foraminifera. Mr. Guppy adds to 

 the list of species found in other West Indian Miocene beds 

 Solarium quadriseriatum, Sow., species of Turritella and Pecten, 

 and teeth of a fish apparently closely allied to Sj)hce7'odus gigas ; 

 also eight species of echinoderms,^ namely : Ecliinolampas seiniorhis^ 

 Guppy, closely allied to E. heviisphcericus, Lam. of the Maltese 

 and other Miocene localities ; E. lycojpersicus, Guppy, near E. scuti- 

 formis, Leske, of Malta and elsewhere ; Schizaster Scillce, Desmoulins, 

 also found in Malta ; Echinoneus cyclostomus\ Leske and Brissus 

 dimidiatus, Agassiz, both living species but rarely found fossU in 



^ Quart. Journ. Geol. Soc. vol. xxii (1866) pp. 297-30L 



