SEPTEMBER 13, 1918] 
relations of the contractor to both the pro- 
ducer and consumer are well portrayed, and 
the many and almost insurmountable problems 
of bringing milk to the doors of the consumers 
in as pure a state, and as quickly as possible, 
without prohibitive cost, are clearly presented 
and discussed from every possible angle. The 
pages in the last chapter on municipal and 
state control of milk production and distribu- 
tion, with types of ordinances as examples, 
should be of much interest to health officers 
and milk inspectors. The practical applica- 
tion of scientific principles to milk production, 
and the different bacteriological and chemical 
methods and standards for controlling the 
purity of milk, receive their due share of at- 
tention. The book concludes with a discus- 
sion of infant mortality. 
It is unfortunate that grammatical errors 
should have been allowed to creep into the 
book here and there, as for example the fol- 
lowing: “Enough data has been collected” 
(page 180), and “the relations between the 
farmer and city milkman 7s delicate”; and in 
the use of scientific names, as for instance in 
“ streptococci, staphylococci and bacteria were 
found.” A very common error in punctuation 
is the absence of the comma between the prin- 
cipal parts of a compound sentence, especially 
where the conjunctive “but” is used. These 
are, however, but minor defects which will 
undoubtedly be eliminated from future edi- 
tions. 
The author does not claim originality, but 
as he states, has drawn from a wide field of ex- 
perience of others, experts in their own do- 
_main, who have been given full credit, and to 
whose work references are given at the end of 
the individual chapters. Throughout the book 
original tables and illustrations materially add 
to its value. Leo F. Retrcer 
SHEFFIELD ScienTIFIC SCHOOL, 
YALE UNIVERSITY 
SPECIAL ARTICLES 
CORPUS LUTEUM AND THE PERIODICITY IN 
THE SEXUAL CYCLE 
In a recent paper G. W. Corner and F. H. 
Hurni report on experiments in which they in- 
SCIENCE 
273 
jected intraperitoneally rats with suspensions 
of corpus luteum preparations.? In all but one 
animal the substance prepared by Armour & 
Company was used. 
While Corner and Hurni find that such in- 
jections may cause peritoneal adhesions and 
peritonitis, they failed to inhibit ovulation. So 
far the experiments of these authors are essen- 
tially in agreement with the results not men- 
tioned by Corner and Hurni which I previ- 
ously obtained in guinea-pigs.2 I stated: 
While in some injected guinea-pigs ovulation was 
apparently delayed, in others it took place at the 
expected term despite the fact that these animals 
had repeatedly received large doses of lutein. We 
may therefore conclude that injections of lutein 
extract can not wholly take the place of the living 
corpus luteum. Whether or not they can do so 
partially in mammals, I am not prepared to say 
on the evidence at hand. 
Some details as to doses used in these ex- 
periments are found in a paper in which in 
conjunction with Dr. Cora Hesselberg I re- 
ported on the effect of such injections on the 
cycle of the mammary gland in the guinea- 
pig.3 
Our experiments on the effect of injections 
of corpus luteum substance had been suggested 
through positive results which R. Pearl and 
Surface had previously published concerning 
the retarding effect of such injections on the 
ovulation in birds.+* 
We emphasized the negative character of our 
results, because a slight delay in ovulation 
ean be induced in the guinea-pig through vari- 
ous experimental interferences, and especially 
did we find that undernourishment prevented 
the normal maturation of follicles.® 
The experiments in which ovulation oc- 
1George W. Corner and Felix H. Hurni, Amer- 
ican Journal of Physiology, 1918, XLVI., 483. 
2Leo Loeb, ‘‘Surgery, Gynecology and Obstet- 
rics,’? 1917, XXV., 300. 
3 Leo Loeb and Cora Hesselberg, Journal Exper, 
Medicine, 1917, XXV., p. 305. 
4Raymond Pearl and F. M. Surface, Journal 
Biol. Chem., 1914, XIX., p. 263. 
5 Leo Loeb, Biological Bulletin, 1917, XXXII, 
p. 91. 
