308 Mr. F. Chapman on 
and consists of a coarse brownish sand, the larger grains of 
which are more or less perfect examples of various forms of 
Stacheia and Nodosinella, the organisms constituting about 
8 per cent. of the natural rock. 
This coarse material, consisting of the fragments of Stacheta 
and Nodosinella, was tested for chitin, since the microscopic 
structure of the test has all the appearance of such. ‘The 
chemical analysis, however, gave no evidence of the presence 
of chitin; and therefore it seems conclusive that the delicate 
areolate tissue observed in these fossils, though originally 
chitinous, has been chemically replaced by another substance. 
For this analysis I am indebted to Mr. W. Tate, F.C.S., of the 
Royal College of Science. Also, with a view of obtaining 
information regarding the nature of the intricate tissue of 
the test of Stacheia, staining was resorted to, for which 
purpose a specimen of S. dispansa was treated with a solution 
of methylene blue, and, after being washed and dried, cut for 
a microscopic section. Examined under a }-inch objective 
the section evidenced staining throughout the cementing tissue, 
whilst sand-grains and sponge-spicules with other mineral 
substances worked into the test were left clear. 
The finer material from the washings consists almost 
entirely of the tests of minute and obscurely septate specimens 
of Haplophragmium, the tests of which are constructed of 
ferruginous and quartzose particles. In the washings there 
are also occasional quartz-grains with well-rounded outlines. 
Bed no. 6.—Blue sandy clay, with ferruginous partings, 
but with the latter character not so marked as in bed no. 5. 
The washings consist of a somewhat fine sand, with ferru- 
ginous or limonitic particles, a few angular quartz-grains, 
some glauconite-grains, and a few bone-fragments. ‘There 
are also some examples present of arenaceous Foraminifera, 
such as [laplophragmium and Ammodiscus, but they are not 
abundant. 
Bed no. 9.—TVhis bed is known as the ‘‘ Wedmore Stone.” 
Three distinct varieties were examined in thin sections. The 
specimens are compact limestones. One of these is of a 
yellowish-brown colour, and is composed chiefly of remains 
of molluscan shells; it is, however, much altered and partly 
recrystallized. A microscopical section of this specimen 
showed a globose-chambered foraminifer which has the outline 
of Nodosaria radicula (L.), and there were also many frag- 
ments of similar organisms, but with no specially recognizable 
characters. 
The second specimen is of a bluish-grey colour, and, seen 
under the rnicroscope, it appears to consist of finely crystal- 
