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SCIENCE 



[N. S. Vol. XLIII. No. 1114 



Wliile detailed directions for " experimental 

 processes " (that is, analyses to be performed) 

 are numerous, the usefulness of the manual is 

 by no means limited to these, since the range 

 of processes discussed in the text is exceed- 

 ingly wide. The richness of the author's ex- 

 perience is reflected in many unusual sugges- 

 tions as to technique and reagents, such, for 

 example, as the employment of anthracene 

 filters, and the use of sodium tungstate as an 

 absorbent. The treatment of such topics as 

 the variations in solubility of precipitated 

 substances under varying conditions, colloids, 

 the washing of precipitates, electrolysis, nor- 

 mal solutions and indicators is broad and 

 scientific, and should give the thoughtful stu- 

 dent a clear notion that analytical chemistry 

 is not only much more than a question of 

 manual skill, but something demanding his 

 best intellectual efforts. In a few instances, 

 notably the basic acetate process, the explana- 

 tion of the part played by the various reagents 

 might to advantage be somewhat elaborated. 



The book is a noteworthy and valuable addi- 

 tion to the literature of analytical chemistry. 

 It contains much that is of novel interest to 

 a more experienced analyst, but it is probable 

 that many teachers will question whether a 

 beginner, lacking a background of experience, 

 will be able to appreciate and use the descrip- 

 tive material which is included in the text, 

 but not directly applied to definite analyses. 

 This material is, however, so arranged as to 

 permit of selection, and it is all stimulating 

 to the interested worker. 



H. P. Talbot 



The Embryology of the Honey Bee. By James 

 Allen Nelson, Ph.D. Princeton IJniversity 

 Press, Princeton, N. J., 1915. 

 A monograph of 282 pages with 95 figures 

 in the test and six plates is an achievement in 

 itself even when one deals with a compara- 

 tively well-known subject; but the present 

 monograph is not simply a compilation. Dr. 

 Nelson has incorporated in this work a great 

 deal of his own research and many original 

 observations. His account of the work done 

 by others is accurate and, while preserving his 



own point of view, he displays in his criticism 

 the admirable quality of abstaining from per- 

 sonal remarks which so often mar the pages 

 of scientific papers. 



It would be very diificult to review the whole 

 book in detail since many chapters naturally 

 deal with facts already known to science, 

 which merely find their confirmation here. I 

 shall therefore endeavor only to emphasize 

 some of the observations new to science and to 

 point out certain shortcomings in this other- 

 wise excellent book. Thus, in the chapter on 

 cleavage, ISTelson makes the interesting state- 

 ment that " the size of the nuclei is, in a 

 given egg, quite uniform from the beginning 

 to the end of the period under consideration, 

 hut varies considerably in different eggs, 

 ranging from 9-14 microns" (p. 21) (italics 

 are mine). In every other respect Nelson's 

 observations on cleavage are in harmony with 

 those of other investigators. The figures ac- 

 companying this chapter are fairly good, but 

 the addition of a figure representing a sagittal 

 section through an egg at the end of the cleav- 

 age process would have been advisable. The 

 chapter on the formation of the rudiments of 

 the mid-intestine is accompanied by excellent 

 figures and gives new support to the opinion 

 expressed by the reviewer and others that the 

 mesenteron is derived from the mesoderm, al- 

 though Nelson believes that a choice is pos- 

 sible between this interpretation and that of 

 Carriere, according to which the mesenteron 

 rudiments may be considered to be purely 

 blastodermal in origin, such a choice depend- 

 ing " largely on the theoretical bias of the 

 interpreter." In the next chapter Nelson 

 comes to the conclusion that both the " Ez " 

 cells described by the reviewer and the " yolk 

 plug " are identical with the " cephalo-dorsal 

 body." This affords the reviewer an oppor- 

 tunity to state that he, too, is now of the same 

 opinion. That the reviewer has never before 

 come out with a statement to this effect, is 

 due to the unusually personal note struck by 

 his critics, even to an insinuation of motives 

 other than a desire to find out the truth. In 

 such cases silence seems always to be the best 

 answer. With the fall of the interpretation 



