506 J. U. Coolie — Globigerina Limestones of Malta. 



this bed; but below this, Aturia does not seem to occur, its place 

 being taken by a large nautiliform cephalopod, many casts of which 

 may be seen in the Valetta Museum. 



Division F. — The rock of this division is a yellowish, soft-textured 

 limestone, homogeneous and fine-grained, and composed for the most 

 part of minute, thin-shelled tests of foraminifera. The formation 

 extends throughout the islands, but it varies in thickness from 

 50 feet in the western parts of Gozo to 30 feet in eastern Malta. 

 A characteristic feature of the bed is the quantity of siliceous 

 concretions which occur in the lower parts of the formation. These 

 concretions have already been described. 1 The upper portion of this 

 bed is not prolific in fossils, but in the lower part, and especially 

 in and around the pockets of phosphatic nodules, numbers are to be 

 found in a good state of preservation. The mollusca are numerously 

 represented : Pecten denudatus, P. spinulosus, P. cristatus, Conns 

 dubius, C. Russigeri, and casts of Area are very common. Of the 

 corals, the eight species that occur in the overlying beds are also 

 found here. 



The remains of cetaceans and sharks are common, and it was 

 from this horizon that the teeth and vertebras of Phoca rugosidem 2 

 were obtained. It is noteworthy that no Scalariee have been found 

 below this bed. Cirsotrema retusa, C. Ducei, and C. pumiceum were 

 found above the third nodule seam, but they were rare. Another 

 interesting fossil which seems to make its first appearance here is the 

 pteropod Cavolina Coolcei, Simonelli. 3 Its vertical range is very 

 limited, as it appears to be strictly confined to this horizon. The 

 pockety phosphatic seams at Kala and Xeuchia in Gozo j'ield 

 it in comparative abundance. During the construction of the new 

 dock at Burmola, numerous ribs, vertebras, and teeth of reptiles 

 having crocodilian affinities were discovered in this bed. A portion 

 of a skull of Tomistoma ehampsoides with teeth in situ and with two 

 vertebras imbedded by the side of it were obtained from the lower 

 portion of the bed by the Dock engineer, and were presented by him 

 to the Valetta University. Several large pieces of amber, of a dirty 

 brown colour and semi-opaque, were found imbedded in the rock 

 at the same place. 



Division G: the third nodule seam. — This layer of phosphatic 

 nodules forms a well-marked horizon in the strata of Malta and Gozo. 

 The nodules are small, and they have a greenish lustre due to the 

 presence of glauconite and phosphate of iron. In chemical com- 

 position they vary considerably, those portions of the seam being 

 the richest in phosphoric acid which are the more compact and 

 fossiliferous. The following analysis made by Mr. J. P. Walton, 

 A.R.S.M., represents the average composition of the bed : — 



1 Cooke, J. H., "On the Flint and Chert of the Globigerina Limestones of the 

 Maltese Islands" : Geol. Mag., Dec. Ill, Vol. X, 1893, p. 157. 



2 Ibid., "On the occurrence of Phoca rugosidens, Owen, in Maltese Strata" : 

 Geol. Mag., Dec. IV, Vol. II, May, 1895, p. 215. 



3 Simonelli, V., " Sopra un nuovo pteropod del miocene di Malta": Bol. del. 

 H. Com. Geol. d' Italia, June, 1894. 



