1010] ACRICULTl'llM. BOTANY. 323 



The results are said to Indicate thai 2 per rent of borax in a fertilizer used 

 at the rate of 100 lbs. per acre in the row will bleach the leaves of the corn 

 plant and cause more or less permanent injury. 



Crops thrive under Imhoff-tank sludge tests at Dallas, C. Savii.i.k {Engin. 

 Neirs-Ix'a:, 81 (1018), No. 4, pp. 16J h 165; abs. in Chem. Aba., 12 (1918), No. 22, 

 p. 2^01). — In tests of the sludge with peanuts, eowpeas, corn, and cotton, grown 

 <in sandy loam which had B tendency to bake in dry weather, it was round that 

 the growth of corn and cotton was Increased and that the physical condition of 

 the soil was materially improved. 



AGRICULTURAL BOTANY. 



The effects of inbreeding and crossbreeding upon development, D. F. Jones 

 (Connecticut State Stn. Bui, 207 (191S), pp. 8-100, pis. 12, figs. 3).— This bul- 

 letin, which was prepared as a thesis to be presented to the faculty of Bussey 

 Institution of Harvard University, is a progress report on inbreeding and cross- 

 breeding. The experiments on inbreeding of maize, on which much of the bul- 

 letin is based, were conducted at the station by the author and others. Exten- 

 sive reviews of literature are given, the experimental work with maize men- 

 tioned above is described at length, and the theoretical importance of inbreeding 

 is pointed out. After a summary showing the effects of inbreeding and cross- 

 breeding, the author gives a Mendelian interpretation of heterosis and describes 

 the part It has played in the establishment of sex. 



In conclusion, the author states that the good or bad results of inbreeding 

 depend solely upon the constitution of the organisms before inbreeding is com- 

 menced. Inbreeding is concerned only with the manifestation of conditions pre- 

 existing. As a means of analyzing and of purifying a cross-bred stock by the 

 elimination of undesirable qualities, inbreeding is therefore a method of first 

 importance in plant and animal improvement. 



The relation of mutational characters to cell size, W. W. Tupper and H. H. 

 Bartlett (Genetics, 3 (1918), No. 1, pp. 93-106, figs. 2). — Reporting a continu- 

 ation of the study previously noted (E. S. R., 36, p. 222), the authors claim to 

 have shown that what is thought to be a mutant of Oenothera gigas or (E. semi- 

 gigas may be a cell giant and at the same time a half dwarf. The half-dwarf 

 habit of the mutant latifolia is due not to its being composed of smaller but of 

 fewer cells, and results from a life cycle shortened not as to duration but as to 

 number of cell divisions. 



From a comparison of the form typica and the mutant gigas, they conclude 

 that the supposed tetraploid forms have much larger cells and are differentiated 

 from typica by characters of organization as well as of proportion. It is 

 impossible to be certain which characters are due directly and which Indirectly 

 to the doubling of the number of chromosomes. The Cad that the supposed 

 gigas mutations differ widely among themselves, some apparently belonging to 

 the category of half dwarfs, suggests that some characters may be independent 

 of the doubling and due to an independent mutation at the time of origin of 

 the tetraploid number. 



The nature and signification of the chondriome, A. din t.ii.'.mond (Compt. 

 Rend. Acad. Sci. [Paris'], 166 (1918). No. 16. pp. 6J t 9-651 ) .— On account of con- 

 tradictory views among observers regarding the chondriomes and on account 

 of their supposed importance in cellular physiology, the author discusses 

 briefly the distinctive characters, relations, and functions of mitochondria and 

 the technique appropriate to their demonstration. 



111401°— 19 3 



