Reviews— Hutchinson's Extinct Monsters. 41 
taken as a zonal index, is not recorded by Mr. Roberts. He refers 
‘later on (p. 77) to the grouping adopted by Prof. Phillips, and 
remarks that the Oxford classification would apply equally well for 
the Cambridgeshire district. We may take it, therefore, that Mr. 
Roberts intended simply to indicate the local zones, without implying 
that they would be of general application. 
Turning to the Corallian Rocks, a careful study of the fossils 
shows that the Hlsworth and St. Ives Rocks are approximately of 
the same age, and that they represent, in part at any rate, the 
Lower Calcareous Grit of other areas; a conclusion that bears out 
the views expressed (with less confidence) by Messrs. Blake and 
Hudleston. 
Overlying the Elsworth rock is the clay denominated Ampthill 
Clay, by Prof. Seeley, and this formation and its fossils are very 
fully described, so far as the area near Cambridge is concerned. 
The evidence goes to show that in mass this Clay represents the 
Upware Limestone, thus including both Coralline Oolite and Coral 
Rag. The general assemblage of fossils agrees in this view, which 
would include these beds in the zone of Ammonites plicatilis. The 
occurence together of Ostrea deltoidea and Gryphea dilatata in the 
Ampthill Clay, serve also to connect it with the Corallian Rocks, 
for both species occur in those strata in Dorsetshire. Prof. Seeley 
had placed the Upware Limestone above the Ampthill Clay. 
Another point of interest in Mr. Roberts’ work, is the fixing of 
a plane of division between the Ampthill Clay and the Kimeridge 
Clay. Phosphatic nodules had previously been noticed in the 
Kimeridge Clay, but it had not been seen that they occur in a fairly 
constant manner at the base of it. The Lower Kimeridge Clay is 
well developed in the district, but the author has been unable to 
detect any Upper Kimeridge, unless it be in the uppermost part of 
the section at Roslyn Hill. The occurrence of Ammonites biplea, 
Lucina minuscula, Discina latissima, and other species, would seem 
to justify a more confident opinion with regard to the Upper 
Kimeridge ; as is indeed held by Prof. Blake. 
Concluding portions of this work deal with the Correlation of the 
strata with other English deposits, and with those in the Paris 
Basin, the Jura, and the neighbourhood of Hanover. The very full 
lists of species, all so carefully verified, from many localities and 
horizons in these Upper Jurassic Rocks, will render the work most 
valuable to all workers on the subject. 
IIJ.—Extinct Monsrrrs: A Porutar AccOUNT OF SOME OF THE 
LARGER FORMS OF AncrieNT Antmat Lire. By the Rev. H.N. 
Hurcuinson, B.A., F.G.S., with Illustrations by J. Smit and 
others. London: Chapman and Hall, 1892, 8vo. with 24 full- 
page Illustrations and 38 Illustrations in the text; pp. xx and 
204. (Price 12s.) 
AN is distinguished from other animals by the higher develop- 
ment of his mental faculties, and one of the earliest lines along 
which his thoughts have’ever delighed-to travel, beyond the mere 
