322 
ally being attacked, sometimes openly, some- 
times insidiously. It is all-important, there- 
fore, that medical men and women should 
band themselves together for the common pro- 
tection of themselves and the profession to 
which they belong, and to this end join the 
British Medical Association. For the objects 
of this body are to promote the progress of 
medical science and the interests of the med- 
ical profession, and its past history shows that 
it has well fulfilled them.—The British Med- 
acal Journal. 
SCIENTIFIC BOOKS 
The Wings of Insects. By J. H. Comstoor. 
Ithaca, N. Y., The Comstock Publication 
Company. Pp. xviii-t 423, 9 plates and 
497 figs. 
In these days of distraction from pure sci- 
ence it is a pleasure to note the appearance 
of Professor Comstock’s book on the wings of 
insects. The whole book is devoted to an ex- 
position of the uniform terminology of the 
wing veins of insects, a field of scientific re- 
search in which Professor Comstock has long 
been preeminent. The book is founded upon 
the now well-known theory that the wing 
veins of insects can only be homologized by a 
study of the trachex which precede them. The 
historical phases of this theory are discussed 
together with the general features and devel- 
opment of the wings of insects. A general 
chapter that ought to be appreciated is the 
one on paleontological data. Professor Com- 
stock’s conclusion after. reviewing the various 
fossil forms is: “A study of the paleontolog- 
ical data confirms to a remarkable degree the 
conclusions drawn from the study of the 
ontogeny of living insects as to the probable 
primitive type of wing venation.” 
Following the general chapters are special 
chapters devoted to the wings of the various 
orders of insects. In these chapters the 
author has not only used the results of his 
original investigations but has also used the 
results of various workers who haye given 
special attention to the different groups. 
These two, sources of information have been 
welded into a concrete whole that taken to- 
SCIENCE 
[N. 8. Vou. XLVIII. No. 1239 
gether with the illustrations both of wing 
tracheation and venation can not help but 
convince entomologists not only of the desir- 
ability of a uniform terminology but also of 
the firmness of the foundation upon which 
the Comstock system is based. 
Z. P. Mercar 
STATE COLLEGE, 
West RaeicH, N. C. 
THE PROCEEDINGS OF THE NATIONAL 
ACADEMY OF SCIENCES 
Tue. fourth number of Volume of the Pro- 
ceedings of the National Academy of Sciences 
contains the following articles: 
Dynamical aspects of photosynthesis: W. J. 
V. OsterHout and A. R. C. Haas, Laboratory 
of Plant Physiology, Harvard University. 
Ulva, which has been kept in the dark begins 
photosynthesis as soon as it is exposed to sun- 
light. The rate of photosynthesis steadily in- 
creases until a constant speed is attained. 
This may be explained by assuming that sun- 
light decomposes a substance whose products 
catalyze photosynthesis or enter directly into 
the reaction. Quantitative theories are devel- 
oped to account for the facts. 
Mobilities of ions in air, hydrogen and nitro- 
gen: WKta-Lox YeENn, Ryerson Physical Lab- 
oratory, University of Chicago. Extensive ex- 
periments, the rusults of which are in perfect 
accord with the “small-ion” hypothesis, .as 
contrasted with the “ cluster ” hypothesis. 
Thermo-electric action with dual conduction 
of electricity: Epwin H. Hatn, Jefferson 
Physical Laboratory, Harvard University. A 
continuation of previous papers. The hypoth- 
esis of progressive motion by the “free” elec- 
trons only has been extended to the case of 
dual electric conduction. 
Terrestrial temperature and atmospheric ab- 
sorption: O. G. Appor, Astrophysical Observa- 
tory, Smithsonian Institution. The earth’s 
surface sends out 0.50 calorie per cm? per 
minute on the average, and of this only a 
small part escapes to space. Hence, the at- 
mosphere is the main radiating source, furn- 
ishing three fourths of the output of radiation 
of the earth as a planet. 
