308 NATURAL SCIENCE [November 



In this clay there is a fair quantity of minute glauconite grains, 

 found only in the finest washings. The foraminifera yield evidence 

 of slightly shallower conditions than the preceding, which, however, 

 is probably placed at too great an estimation, since the foraminifera 

 obtained from the green-sand seam, as previously pointed out, are not 

 numerous enough to be representative. 



The depth for this deposit is 700 fathoms. For comparison, one 

 may refer, as a typical green mud of similar depth, to ' Challenger,' 

 Station No. 163 F., off Sydney, depth 650 fathoms. 



Zone II. — The samples taken from this zone were clays of a 

 dark green colour. 



The residua yielded a fair quantity of glauconite, and the pre- 

 sumably pelagic Globigerina cretacea was met with in some frequency. 

 In their general character these clays are comparable with the green 

 muds. 



The depth of these samples works out at 820 fathoms. 



Zone III. — The clay of this zone is of a pale brown or fawn 

 colour, and is quite distinct in appearance from the rest of the Gault. 

 Glauconite is extremely rare, and appears to be entirely absent in 

 the modern red muds, with which this clay may perhaps be com- 

 pared. The comparison, however, is not much more than one of 

 similarity of colouration in its present condition, for much of the 

 colour in modern red muds is due to ochreous matter, whilst that of 

 the Gault of this zone is due to carbonate of iron with some ochre- 

 ous staining. It is, however, not very probable that it could have 

 originally been a blue mud, since this would have resulted, as with 

 some other samples of the Gault, in the infilling of the foraminifera! 

 shells with pyrites instead of carbonate of iron, of which we here 

 have evidence. This carbonate of iron is found in some quantity 

 disseminated through the clay as minute casts of organisms ; and 

 there are also concretionary bands of the same material running 

 through the bed. This concretionary iron band is perforated 

 throughout with what are apparently annelid borings, and this has 

 been noticed by Mr Hilton Price (5), who drew attention to it in 

 1876 in connection with a similar annelid bed which Professor 

 Eupert Jones had described (3) from Westwell Leacon in Kent, and 

 locally known as ' Harper.' This bed Professor Jones found in the 

 " upper part of the lowest third of the Gault " at that locality ; and 

 he compared it with a bluish-grey mud with annelids found forty 

 miles S.E. of No-Sima Lighthouse, Japan, at a depth of 1875 

 fathoms. Professor Jones has been good enough to give me a speci- 

 men of the annelid rock from Westwell Leacon, and I find it com- 

 parable with a similar bed which I found some years ago in the 

 Gault at Godstone. All three specimens probably occur at about 

 the same horizon of the Gault and are equivalent to Zone III. at 



