Junk, 1920| GENETICS 317 



plasm as a unit, its structure identical with the structure of the cell. New contributions to 

 the subject, from cytology, from experimental genetics and from the chemistry of colloids, 

 are discussed with the conclusion that "the old attempts to solve the problem of protoplas- 

 mic behavior by the assumption that it is composed of physiological units, biophores, deter- 

 miners, plasomes, pangens, etc., and the newer conception that its essential elements are unit 

 factors, are being merged in the conception that the structure of protoplasm is the structure 

 of the cell as an organized system and itself the unit in all the complex interactions by which 

 the egg develops into the specialized and differentiated many-celled organisms." [See Bot. 

 Absts. 3, Entry 1934.] — Margaret C. Ferguson. 



2134. Harris, J. A., and F. G. Benedict. A biometric study of human basal metabolism. 

 Proc. Nation. Acad. Sci. [U. S. A.] 4: 370-373. 1918. — Determinations were made on 333 

 normal human individuals, men, women, and infants, of the heat production in the post- 

 absorptive state and in complete muscular repose. The relationship between heat produc- 

 tion and pulse rate, stature, and body weight was studied; correlation was found to exist 

 between heat production and each of the other measurements, but to be insignificant between 

 pulse rate and stature or body weight. Equations are given showing the decrease in heat 

 production with age. The metabolism of women was found to be lower than that of men even 

 when corrected for age, weight, and stature; the difference between the sexes was not evi- 

 dent in infancy but was well marked throughout adult life. It was found that contrary to 

 the belief that heat production is "proportional to body surface but not to body weight," 

 it was found to be highly and about equally correlated with body weight and body surface. 

 Regression equations involving stature, weight, and age are given for the prediction of the 

 daily heat production. — Slyvia L. Parker. 



2135. Harrison, J. B. Seedling sugar canes. Agric. News, [Barbados] 17:289-290. 

 1918. Also in Internat. Sugar Jour. 20: 558-559. 1918. — Various problems arising out of the 

 production of sugar cane seedlings are discussed. It is easy to raise new varieties of high 

 promise as plant canes, but difficult to produce types which will do well under a long rat- 

 tooning system. Seedling canes show a tendency towards senile degeneration. The best 

 seedlings have been raised from parents possessing both vegetative vigor and high sac- 

 charine content. In the West Indies the raising of new varieties by cross fertilization does 

 not seem very promising, owing to the extremely heterozygous nature of West Indian varie- 

 ties. In countries where relatively homozygous kinds are available, the application of Men- 

 delian methods in raising seedlings may be of value. — S. C. Harland. 



2136. Hartog, Marcus. Parthenogenlse artificielle et germination. [Artificial par- 

 thenogenesis and germination.] Scientia 26: 17-27. 1919. — Phenomenon to be explained is 

 not development of egg, but its repose until stimulated. Inactivity is due (as in seeds prior 

 to germination) to inability to use food reserves. When fusion with sperm starts develop- 

 ment, initiation is due (1) to introduction of enzyme by sperm, (2) to production of enzyme 

 by sperm after it enters, or (3) to production of enzyme by egg on stimulation by sperm. 

 Enzyme for digestion of reserves in many cases can be produced without entrance of sperm. 

 Development without participation of sperm should not be called "fecundation" or "fer- 

 tilization," but "induced parthenogenesis," and the means of inducing it "activation." 

 Studies in induced parthenogenesis have contributed no new facts to knowledge of nature 

 of life. — A. Franklin Shull. 



2137. Haviland, Maud D., and Frances Pitt. The selection of Helix nemoralis by 

 the song-thrush (Turdus musicus^. Ann. Mag. Nat. Hist. 3: 525-531. June, 1919. — Authors 

 criticize the conclusion of Trueman (Ann. Mag. Nat. Hist., Oct., 1916) that T. musicus 

 selects light-banded shells of H . memoralis, on the grounds that (a) H. aspersa as well as 

 H . nemoralis is eaten, (b) there may be differences in the snail population in localities from 

 which the shells found broken at the "anvils" (at which the birds habitually break their 

 shells) and those from which the control collections were made, and (c) that there is no con- 

 clusive evidence of selection when snails of different pattern are exposed in the open or offered 

 to the bird in confinement. — /. Arthur Harris. 



