THE GEOLOGY OF THE ENGLISH CHANNEL. 157 



Verneuilina and one of Textularia, both the latter with arenaceous 

 tests. Biloculina ringcns is clearly present, and apparently a species 

 of Polymorphina and one of Spiroloculina. There are several sections 

 of a very beautiful foraminifera, all, however, in planes practically 

 parallel to that of its spiral ; still, cut at diflerent parts of the thick- 

 ness of the test, they give fairly clear information as to the form. It 

 is certainly Planorhidina, and seems identical with Planorhidina 

 larvata, Parker and Jones. This species is, however, only hitherto 

 known as recent and of tropical habitat. The rock is too hard to 

 admit the separation of the foraminifera as opaque objects, and 

 sections must be relied upon wholly ; so far three have been prepared, 

 but many more will have to be cut before any certain identifications 

 of the foraminifera can be made, except among the Miliolinm and in a 

 few chance instances where typical forms are fully displayed. Glau- 

 conite grains are common and of fair size, and the same mineral fills 

 the chambers of many of the foraminifera. The foraminiferal shells 

 have not been the subject of any mineral alteration. The ground- 

 mass of the rock has been a highly calcareous mud, with little 

 aluminous matter. Comparatively shallow water conditions and a 

 warm sea are indicated. (Plate XI and Plate XII, figs. 1 and 2.) 



ROCKS OF UNDETERMINED AGE. 



SANDSTONE. 



M. 14d. S. 24" W. Edd., 20 miles. 



A buff-coloured sandstone with calcite cement, appears rather open- 

 textured on outer face of pebble, but is quite compact within. 



By far the greater number of grains are quartz, but a few felspars 

 show in the slide. There are also some shell fragments and other 

 organic remains. Many quartz grains show acicular crystals of apatite, 

 some few have zircon enclosures. Some are nearly free from fluid 

 inclusions, but most show rather many, with bubbles in the majority 

 of instances. Many of the grains are iron-stained yellow along cracks, 

 obviously before inclusion in this rock. 



This rock has all the appearance of a ragstone, and may very 

 possibly belong to the Neocomian formation. 



ARKOSE. 



M. 62x. S. 42^ W. Edd., 464 miles. 



The fracture shows a pale pink rock ; externally tlie worn surface 

 looks rather like sandstone in which the cementing material is less 

 hard than the sand grains, the fractured surface seems more 

 like a granular f el site; felspar of a light flesh colour is clearly 

 visible. 



