440 THE ZOOLOGIST. 



NOTICES OF NEW BOOKS. 



The Cambridge Natural History. Vol. I. Protozoa, by Marcus 



Hartog, M.A. ; Porifera, by I. B. J. Sollas, B.Sc. ; Coelen- 



terata and Ctenophora, by S. J. Hickson, F.E.S. ; Echino- 



dermata, by E. W. MacBride, F.E.S. Macmillan & Co., 



Limited. 



Vol. I. of this excellent series of volumes has now appeared, 



and if out of sequence is still in due season, for the authors have 



brought their subjects well up to date. In reading this volume 



we are firstly impressed with the wide field of our study which is 



practically absent from the pages of ' The Zoologist,' for few of 



our contributors apparently study these frequently minute, and 



what we generally regard as primitive, forms of animal life. 



And yet with the Protozoa an evolutionist may study his first 



lesson in the endeavour to find a primary division between 



" animals " and " plants." An ox standing under a tree affords 



a sufficient distinction for an ordinary man, but to the zoologist 



engaged in the study of some Protozoa the problem is virtually 



unsolved, at least so far as the result can be expressed in words ; 



and, as Mr. Hartog remarks, "the study of the Flagellates has 



been largely in the hands of botanists." Haeckel, with his 



genius for simple but profound division, therefore divides the 



living world into the Metazoa, or Higher Animals ; the Meta- 



phyta, or Higher Plants ; and the Protista, which occupy the 



debatable plane. 



If this problem is not sufficiently profound to the student of 

 the Protozoa there is still another — the question of Spontaneous 

 Generation — and Mr. Hartog, in discussing this matter of heated 

 contest, gives a very judicial opinion, and one we gladly repro- 

 duce : " Of the ultimate origin of organic life from inorganic life 

 we have not the faintest inkling. If it took place in the remote 

 past, it has not been accomplished to the knowledge of man in 

 the history of scientific experience, and does not seem likely to 

 be fulfilled in the immediate or even in the proximate future." 

 There are, however, zoologists who are happily free from 

 these considerations, and who seek a knowledge of animal life as 

 it is, without the contemplation of "origins." In this beauti- 

 fully illustrated volume they will find what they desire. The 

 contributors are not only competent authorities, but in these 

 pages have taken pains to not only give us their own experience, 

 but to tell us what is known ; and if the volume relates to animal 

 organisms not so generally studied as they deserve to be, it is 

 likely to promote, in the minds of many naturalists who have 

 confined their studies to higher animals, an attention to the 

 minute creatures that form the foundation of biology, and are 

 primary factors in the evolutionary conception. 



