131 



THE GEOLOGIST. 



matrix, with calcareous cement. Many of the grains are obscure 

 foraminifera and debris of shells, etc. Mr. Parker has detected the 

 following foraminifera in this matrix i — Globigerina bulloides, Trun- 

 catulina lobatula, Planorbulina ammonoides (Quart. Journ. Geol. 

 Soc, vol. xvi. p. 300), and Calcarina rarispina. 



Dr. Carpenter's allusion to this Heterostegina-rock as being found 

 in fissures in Malta, appears to be incorrect (Introd. Foraminif. 

 Kay Soc, 1862, p. 288). 



In some places this bed contains a large quantity of green grains. 

 These may prove, on examination by the microscope, to be casts of 

 the cells of foraminifera, bryozoa, etc., as Bailey and Ehrenberg have 

 shown other sands of silicate of iron really to be. Captain Spratt 

 and Professor E. Eorbes (Joe. cit.) notice the occurrence of cetacean 

 bones in this bed, and of oysters with the Heterosteginae. 



The bed No. 3, blue marl, about 100 feet thick, is not yet known 

 to contain foraminifera ; but should be examined with careful mani- 

 pulation, as described in the ' Geologist,' vol. ii. p. 214. 



No. 4, the freestone, consists of four or five divisions that run one 

 into the other, lying in no regular order. The building-stone is that 

 in which most of the Echinodermata are found. Captain Hutton 

 and Dr. Adams state that the Heterostegina occurs in the freestone ; 

 the latter points out that it is much rarer than in No. 2, " and only 

 in a drab or light-blue portion towards the upper parts of the bed." 

 In Professor E. Forbes's list (op. cit. -p. 230), Cristellaria and Nodo- 

 saria are said to occur in the upper division of this freestone ; and 

 within the last few days Captain Spratt has obligingly shown me the 

 specimens referred to. They comprise Nodosaria RapJianus, N. Ra~ 

 plianistrum, N. Radicula, Dentalina acicula, D. pauperata, Lingiilina 

 costata, Frondicularia annularis, Cristellaria calcar, and C. cassis. 

 No doubt numerous smaller forms will also be found ; for these are 

 the larger specimens of such a group of foraminifera as D'Orbigny 

 has figured and described in his Foram. Foss. Bassin. Tert. de Yienne. 

 Some of the specimens are yellowish, some are greyish, indicating at 

 least two beds or seams that are rich with them. 



No. 5 is the hard whitish limestone, also used for building ; it is 

 very variable in lithological character, Captain Hutton says, and 

 more than 400 feet thick ; he adds, that " it is at the top of this bed 

 only that Scutella subrotunda is found." I find, by specimens that 

 have been shown to me, that it also contains, in large abundance, 

 Operculina complanata and Orbitoides dispansus. 



The Operculinae (which appear to be two subvarieties) occur gre- 

 gariously in the upper part of the limestone, are associated with 

 Scutella subrotunda and Echinolampas scutiformis, and "are very com- 

 mon at the fault at Migiar Selimi in Gozo, and at various points 

 along the northern coast of Malta." (Dr. A. L. Adams.) A large 

 hand-specimen that Captain Hutton has kindly given me, comes 

 from Marsa Scala, Malta. 



[We must remember that the so-called " Lenticnlites complanatus" 



