116 



THE ZOOLOGIST. 



NOTICES OF NEW BOOKS. 



A Treatise on Zoology. Edited by Sir Kay Lankester, M.A., 

 LL.D., F.K.S., &c. Part I. Introduction and Protozoa. 

 First Fascicle by S. J. Hickson, F.E.S., J. J. Lister, 

 F.E.S., F. W. Gamble, D.Sc, &c, A. Willey, M.A., D.Sc., 

 &c, H. M. Woodcock, D.Sc, the late W. F. E. Weldon, 

 F.E.S., and E. Kay Lankester, K.C.B., &c. 



This volume contains the first fascicle of part i., and is just 

 published ; the second fascicle appeared in 1903, and was then 

 reviewed in these pages. The two fascicles fully bear out the 

 claim made for them by their Editor, that they " give a more 

 complete account of the Protozoa than is to be found in any 

 similar work hitherto published." 



To the ordinary biologist and evolutionist this volume is of 

 the greatest importance, for in the Introduction Sir Eay 

 Lankester discusses " The Dividing-line between Plants and 

 Animals." For the main difference we are directed to the fact 

 that " animals are unable to assimilate — that is, to utilise as food 

 the simpler chemical compounds of carbon or of nitrogen. They 

 can only take their nitrogen from food which is in the elaborate 

 form of combination which is called a proteid ; they can only 

 take their carbon either from a proteid or from a carbohydrate 

 or a hydrocarbon." " Plants, on the contrary, are (with certain 

 exceptions) able to take up as food the compounds of carbon and 

 of nitrogen, which may be called the stable or resting condition 

 of those elements — namely, the simple oxide of carbon — carbonic 

 acid gas, and the simple compound of nitrogen and hydrogen 

 which is called ammonia, or the oxide of nitrogen which forms 

 nitrates." " The obvious and predominant difference in the 

 make and habit of plants as compared with animals is thus con- 

 nected with the very great and definite difference in the nature 

 of the food of the two groups." The debatable ground is limited 

 to the chlorophyll-forming Flagellata, including some for which 

 " it is not possible to draw a sharp line and assign them 



