146 



SCIENCE 



[Vol. LVI, No. 1440 



of Mendelism. The basic facts of cytology 

 were originally treated in the second chapter 

 feut now follow the fundamental facts of 

 Mendelism and prepare the way for an inter- 

 pretation of the "Architecture of the Germ 

 Plasm" according to recent researches. 



To reduce mathematical formute to a mini- 

 mum is a decided advantage to the lay reader 

 to whom these are confusing; but it is perhaps 

 disadvantageous for the college student, whom 

 we seem to be shielding from even moderate 

 mental effort by continually simplifying sub- 

 ject matter. Underlying all distributions of 

 characters in assortative matings are certain 

 elementary principles based on probabilities 

 and the theory of simple sampling. When the 

 student looks upon a Mendelian population in 

 these terms, he has the advantage of a general 

 fundamental law rather than the knowledge of 

 an individual case. The general lack of this 

 element in approaching genetic problems is 

 perhaps more keenly felt than any other one 

 thing. For example, the standard deviation is 

 not used "since for mathematical reasons it is 

 more accurate" (p. 27); but it is more con- 

 venient, and preferable to the average devia- 

 tion because of its relation to probable error. 

 Again, the sum of a set of observed frequencies 

 should equal the sum of the calculated fre- 

 quencies in any given series of observations, 

 but they fail to do so in the ta;ble on p. 157. 

 In discussing the practical applications the 

 author states (p. 119) that "when ten differing 

 characters are combined in the parental gen- 

 eration there would result over a million kinds 

 of possible offspring among the hybrids of the 

 second filial generation, (3 -f 1)" = 1,048,576." 

 While such a hybrid would produce 2^° kinds 

 of gametes which might combine in 2-° = 

 1,048,576 ways, so many duplications of type 

 appear that it is misleading to consider each 

 combination as a separate "possible kind"; 

 and in reality there would be only 2" = 1,084 

 different visible classes (pheno types) and 3^" = 

 59,049 classes differing in germinal constitu- 

 tion (genotypes). At some points, there seems 

 to be confusion as to an exact definition of geno- 

 type. On p. 109, the author states that "There 

 are then . . . nine different genotypes in any 

 dihybrid cross," i. e., 3" where n = number of 

 allelomorphic pairs. This definition agrees 



with the current usage, but is hardly consistent 

 with the usage on p. 153 and p. 159. A num- 

 ber of minor errors which always occur in the 

 most carefully prepared texts will without 

 doubt be corrected in subsequent editions. 



The revised edition maintains the same 

 attractive and readable style of the original. 

 The volume as a whole has a broad usefulness 

 in the related fields of sociology, psychology, 

 education and medicine. Many excellent new 

 diagrams, remarkable for their lucidness and 

 pedagogic value, help the reader to visualize 

 complex groups af fact quickly. Even the 

 experienced teacher of ' genetics will find the 

 volume most suggestive and refreshing. 



J. A. Dbtlepseis" 



University or Illinois 



SPECIAL ARTICLES 



THE EMERGENCY FUNCTION OF THE 



ADRENAL 



We have recently obtained evidence of an 

 emergency function of the adrenal. In some of 

 this work we have confirmed Cannon"^ and his 

 co-workers, who suggested an emergency func- 

 tion for the adrenal. Our method is a modifi- 

 cation of Meltzer's^ denervated eye reaction. 

 The iris is made sensitive to epinephrin by 

 removal of the superior cervical ganglion. Sev- 

 eral days later, in order to eliminate central 

 nervous influence, the ciliary ganglion is re- 

 moved. We have made a study of sixteen cats 

 by this method. 



In most animals prepared in this way, stimu- 

 lation of the moist pinna by rapidly repeated 

 induction shocks will cause a good dilatation 

 of the denervated pupil. Asphyxia for forty 

 seconds will cause almost maximal dilatation. 

 Exposure to cold (immersion in cold water) 

 will usually cause a very decided dilatation 

 after a few minutes, the rectal temperature 

 decreasing meanwhile. As an illustration, a cat 

 whose rectal temperature was 39.0° C. at the 

 start and whose pupil was 0.13 in. in diameter 

 showed the following changes : 



1 Cannon, W. B. : "Bodily Changes in Pain, 

 Hunger, Fear and Eage. ' ' 1915, D. Appleton and 

 Co., New York. 



= Meltzer, S. J.: Am. J. Physiol, 1904, II, 37. 



