March 9, 1893] 



NATURM 



435 



is also seen in the attempt to combine a more general 

 treatment of the subject with practical directions. 



General instructions with regard to the microscope, 

 microtome, and reagents, are given in the introduction ; 

 these, however, do not indicate a very wide personal 

 acquaintance with the ordinary laboratory requirements, 

 and the methods of preparation, &c., are mainly copied 

 from Lloyd Morgan's " Animal Biology " and Howes's 

 "Atlas of Practical Elementary Biology." The student 

 is referred to a number of well-known text-books for 

 further information, but it is curious that no mention is 

 made of certain excellent elementary works treating more 

 especially of the types described. 



The part dealing with plants, which occupies rather 

 more than half the book, is on the whole more satis- 

 factory and contains fewer mistakes than that relating to 

 animals. Most of the woodcuts in the former are taken 

 from well-known sources, and a number of original 

 figures are given of Aspidium and of Lainiurn album, 

 which latter is selected as a type of the Phanerogams ; 

 the author has evidently worked out the structure of these j 

 forms with some care. In the zoological part many of j 

 Lloyd Morgan's diagrams have been utilised, and figures | 

 are also taken from various other text-books, such as 

 Milnes Marshall's " Frog," Wiedersheim's " Comparative 

 Anatomy," and Quain's " Anatomy." Most of those from 

 the last-named work, with the corresponding descriptions, 

 naturally do not refer to the frog at all, but this fact is not 

 stated. Some of the drawings of invertebrates made by 

 the author are very fair, though they do not indicate much 

 originality ; one or two others, such as that of an undis- 

 charged nematocyst of hydra, on p. 221, are bad. The 

 sources from which borrowed figures are taken is not 

 mentioned in all cases, although the contrary is stated in 

 the preface. 



The author shows very little power of selecting his facts, 

 or of drawing conclusions from them in such a way as to 

 clearly illustrate the general principles of the subject. 

 Many of the details, moreover, are incorrect, and errors 

 of the most serious character occur. It will be sufficient 

 to refer to a few of these in order to indicate the author's 

 looseness of expression and want of acquaintance of parts 

 of the subject with which he deals. 



The remarks on the structure and functions of the 

 nucleus, and on the pulsating vacuole in protococcus 

 (pp. 46 and 47) are, to say the least, misleading. This 

 organism may, it is said, " be looked upon as a closed bag 

 with a double wall — the outer of cellulose, and the inner 

 of protoplasm" (p. 50), and the movements of its cilia 

 " probably " drive it through the water (p. 48). The in- 

 vestment of the " spermocarp '' of chara is called a 

 "pericarp," and the pro-embryo a " prothallium " (pp. 88 

 and 89). The description of karyokinesis (p. 108) does 

 not show much knowledge of recent observations. On 

 p. 90, line 10 from top, the word "sexual" has by an 

 oversight been printed as " several." The oosphere is 

 confused with the fertilized ovum on p. 133, although the 

 term oosperm is correctly used on previous and sub- 

 sequent pages. The description of the part played by 

 the nucleus in the processes of reproduction and con- 

 jugation in vorticella on pp. 211 and 212 is somewhat 

 incomprehensible. One gathers on pp. 220 and 221 that 

 it is comparatively easy to distinguish the nerve cells in 

 NO. 1219, VOL. 47] 



hydra in preparations simply traced up in water and 



stained with methyl-blue, and in optical sections of the 

 entire animal prepared with osmic acid. We may 

 mention that it has recently been shown by Albert Lang 

 that the bud in hydra is not " a product of both 

 ectoderm and endoderm " as stated on p. 223. The 

 Metazoa are said to be all " characterized by . . . the 

 possession of a digestive cavity {enteron) " (p. 224). On 

 p. 234 we read that the " kidneys (nephridia) " of the 

 mussel are " sacculated organs whose walls carry a mass 

 of tubules," and one gathers that the small irregular 

 opening leading from the kidneys into the " ureter " is 

 quite easy to recognise. Fig. 194A, representing the brain 

 of the frog, is taken from the old figure by Ecker, in 

 which the " olfactory lobes " are separated by a cleft, and 

 the primary fore-brain is said to be the same thing as 

 the thalamencephalon (p. 333). We do not see the object 

 of introducing a description of the complicated human 

 auditory apparatus in the chapter on the frog. The 

 account of the processes of maturation, fertilization, and 

 segmentation of the ovum of the frog is extremely incom- 

 plete and inaccurate, and one might even infer from 

 one sentence on p. 331 that the nucleus was quiescent 

 during the division of the egg ! We are told that the 

 ectodermic invaginations which give rise to the " nares " 

 become " continuous with the mesenteron " (p. 335). 

 The description of the development of the lungs (p. 334), 

 together with the figure copied from Wiedersheim, 

 refer to the mammal, and not to the frog. In 

 the account of the development of the body- 

 cavity (p. 335), it is said that the latter, " extended 

 upwards through the lateral mesoblastic plates, nearly 

 meets in the middle line beneath the notochord, and so 

 pinches the alimentary canal with its glands into the 

 body cavity " ; and on page 333 it is stated that the 

 notochord "pierces the mesoblast and divides it into 

 right and left halves." The numbering of the Jive 

 aortic arches given in Fig. 225, and that of the three 

 mentioned in the text is incorrect (p. 336). We learn 

 that metamorphosis begins soon after the develop- 

 ment of the gills (p. 336). The account of the 

 development of the urinogenital ducts on p. 338 is 

 quite incorrect as applied to the frog. In Chapter 

 XVIII. one gathers that the processes of digestion 

 in all the Coelomata are quite similar to those which 

 occur in the higher forms, which are then briefly de- 

 scribed. 



Even if we accept the author's dictum that " he will 

 know a good deal of botany who knows Chara and Lamium 

 thoroughly," and give him full credit for having worked 

 up some parts of the subject practically, we must remind 

 him that a wider knowledge than this implies is advisable 

 before attempting to write a book on general biology. 

 After reading the preface and introduction, one is led to 

 expect that the high ideal set up by the author as regards 

 actual personal observation would at any rate have led 

 him to examine carefully and accurately all the types 

 described ; it is very disappointing to find that this has 

 not been the case. In conclusion we venture to repeat 

 Darwin's advice as quoted on p. 200 of this book : " Give 

 full play to your imagination, but rigidly check it by test- 

 ing each notion experimentally." 



W. N. P. 



