Geological Society. 315 



of the " processes " promise well, and appear to have been selected 

 with considerable care ; not a few of them have been repeatedly ve- 

 rified by the constant use of chemists. Terrell's inaccurate method 

 for determining cobalt (p. 151), however, is a decided blemish. 

 Chapter XIV., on gas-analysis, is too short and deficient by leaving 

 out of mention many of the great improvements in the measurement 

 of gases that have been introduced of late years. To the few pages 

 devoted to organic analysis, an account of Ladenburg's method ought 

 certainly to have been annexed. We may add, also, that the author 

 does not, as a rule, by any means sufficiently mark the nature and 

 extent of his own contributions ; and he has given to American 

 methods a prominence which is peculiar and very noticeable. 



Mr. Crookes's book is not without its defects ; but it is the first 

 attempt of its kind, and on that score alone would deserve much 

 allowance. But the extensive verification to which he has subjected 

 his material renders it much more valuable and meritorious. The 

 possession of such a treatise cannot fail to economize the time of 

 the general, but especially of the technological analyst. 



XXXVIII. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 



[Continued from p. 232.] 

 April 5, 1871. — Prof. Morris, Vice-President, in the Chair. 

 fPHE following communications were read : — 

 -*- 1. " On a new Chimaeroid Pish from the Lias of Lyme Regis." 

 By Sir Philip Grey Egerton, Bart., M. P., E.K.S., V.P.G.S. 



This fish, for which the author proposed the name of Ischyodus 

 orthorhinus, was represented by a specimen showing the anterior 

 structures imbedded in a slab of Lias. It exhibited the charac- 

 teristic dental apparatus of the Chimseroids, surrounded with sha- 

 green, a very large prelabial appendage (six inches long, and termi- 

 nating in a hook abruptly turned downwards), and a process which 

 the author regarded as representing the well-known rostral appen- 

 dage of the male Chimaeroid, but in this case attaining a length of 

 5| inches, and covered more or less thickly with tubercles, bearing- 

 recurved central spines somewhat tooth-like in their aspect. This 

 appendage is attached to the head by a rounded condyle, received 

 into a hollow in the frontal cartilage. The dorsal spine, which 

 measured 6 inches in length, was articulated by a rounded surface 

 to a strong cartilaginous plate projecting upwards from the noto- 

 chordal axis, and was thus rendered capable of a considerable amount 

 of motion in a vertical plane. This structure also occurred in 

 Oallorhynchus and Chimcera. 



2. " On the Tertiary Volcanic Rocks of the British Islands." By 

 Archibald Geikie, Esq., E.R.S., E.G.S., Director of the Geological 

 Survey of Scotland, and Professor of Geology and Mineralogy in the 

 University of Edinburgh. — Eirst paper. 



In this communication the author gave the first of a series of 



