564 Reviews — The Sub-Wealden Exploration. 



and a separate anus be formed in another part. (3) The mouth may be, at first, 

 situated out of the centre of the arabulacral canal system, and afterwards removed 

 to it. 



"I believfe that the latter process took place in the development of the orders 

 Cystidea and Crinoidea, In the first formed, or Palaeozoic species, the mouth was 

 not central, but has become so in the existing types." (pp. 91 and 127.) 



These notes are valuable to the student of Palaeozoic Echino- 

 dermata as embodying his own views, and those of other authors. 

 The reader may refer also to Von Buch " On the Cystidea," trans- 

 lated by Prof. Ansted in the Quart. Journ. Geol. Soc. vol. ii., and to 

 Prof. Beyrich, " On the Pelvis of the Crinoidea bracJiiata," translated, 

 by Mr. W. S. Dallas, and published in the Annals Nat. Hist, for 

 June, 1871 ; also to the two valuable papers by Mr. John Eofe, 

 C.E., F.G.S., in the Geological Magazine, 1865, Yol. II. p. 12, 

 and p. 245, PI. VIIL, in which the structure of the Crinoidea and 

 Blastoidea is very fully treated. 



J. M. 



II, — ^Thk Sub-Wealden Exploration. 

 (Second Notice.) ^ 



N a former occasion, when we gave an account of the Sub- 

 Wealden Exploration, a depth of 671 feet had been reached. 

 Since then, according to the Seventh Quarterly Eeport of Mr. 

 Willett, dated June 23rd, 1874, a total depth of 1018 feet has been 

 attained. 



The fossils for the last 50 feet indicate that the Oxford Clay has 

 been reached, thereby fulfilling (so Mr. Willett observes) the 

 dropbecy of the late lamented Professor John Phillips, who stated 

 many months before that " very likely no Oolites or Sandy Eocks 

 may be met with till we touch the unknown Palasozoics." 



The following geological report is given by Mr. W. Topley, F.G.S., 

 Assoc. Inst. C.E., of the Geological Survey of England : 



" In the last Quarterly Eeport some particulars were given of the 

 Kimmeridge Clay, as found in the Boring, down to the depth of 

 656 feet. With some few alterations, to be noted immediately, the 

 description there given applies to the clay which has been pierced 

 since. 



'' A beautiful specimen of Ammonites Jason occurred at about 990 

 feet. Neither this Ammonite nor any ornate form at all resembling 

 it has yet been found in the Kimmeridge Clay. Such Ammonites, 

 however, are amongst the most characteristic fossils of the Oxford 

 Clay; we are, therefore, justified in concluding that the boring is 

 now in that formation. 



"Although the Coral Eag and Calcareous Grit usually lie between 

 the Kimmeridge and Oxford Clays, there are certain localities in 

 which they are absent. This is the case on the north and north- 

 west of Aylesbury; in Lincolnshire; and probably also through 

 the Fen districts. A deep well was sunk many years back at Lynn, 

 in Norfolk ; there the Kimmeridge Clay was found in direct sequence 

 with the Oxford Clay. 



1 For the First Notice, see Geol. Mag. Juae, 1874, p. 261. 



