BOOK NOTICES. 



89 



Lias and Oolites. On the same page the Mammoth is alluded to as 

 if existing throughout the Tertiary period, whereas it only appeared at 

 the close, in Pleistocene times. The Lias is stated to form the cHffs 

 between Robin Hood's Bay and Whitby, but the more important 

 Liassic cliffs from Sandsend to Saltburn are not noticed. Pentacrinite 

 stems are said to be plentifully washed up on the Holderness coast — 

 which is doubtful — and to be derived from the cliffs near Whitby, which 

 is not the case. The Pentacrinites belong to the Lower Lias, which 

 is only exposed in Robin Hood's Bay. The chief source of supply 

 of pentacrinite fossils is at Whitton, near the mouth of the Trent. 

 The majority of mammalia found in the Purbeck beds are said to 

 be marsupial. In fact, they all are. No placental mammal what- 

 ever existed till after Eocene times. A somewhat extraordinary state- 

 ment is made on page 18, that ' the Wealden is another division of 

 the Oolitic system.' On the contrary, it belongs to the Cretaceous. 

 The freshwater beds of the Wealden were contemporaneous with the 

 marine beds of Speeton, and both belong to the Neocomian. It is 

 extremely doubtful if the Speeton Clay appears at all in the district 

 between Market Weighton and the Humber. We may almost predi- 

 cate with certainty that it does not. The black chalk (why called 

 carbonaceous clay?) alluded to on page 21, has been traced over a 

 large area of the Wolds, and probably forms a division between the 

 grey and white chalk. It may be seen on the face of the cliff at 

 Bempton. On the whole, we recommend the paper, and highly 

 commend the object of the writer. The worst fault is the punctua- 

 tion, which can easily be remedied. — E.M.C. 



XXX 



Hand-book of Practical Botany. By E. Strasburger (Professor of 

 Botany in the University of Bonn). Edited from the German 

 by W. Hillhouse (Professor of Botany in Mason College, Birming- 

 ham). London: Swan, Sonnenschein & Co., 1887. 



Of the numerous German text-books of science which have of 

 late years appeared in the English tongue, perhaps none will be more 

 appreciated by the English student than Professor Hillhouse's edition 

 of Strasburger's excellent little hand-book of Practical Botany. 



Until quite recently the total absence of any work on ' practical ' 

 structural botany in the English language, formed one of the most 

 conspicuous lacunae in our scientific literature. This gap was to a 

 considerable extent diminished about a couple of years ago by 

 the appearance of Messrs. Bower and Vines' ' Course of Practical 

 Instruction in Botany,' but there is still room for Professor Hillhouse's 



March 1887. 



