January, 1920] GENETICS 7 



33. Gxttherz, S. Zur Lehre vom Ursprung der tierischen Keimzellen. [To the doctrine 

 of the origin of the animal germ cells. | Arch. Mikroskop. Anat. 92 2 : L-40. Spl.,1 fig, L918. 

 — Aut Imr finds mil osea among oogonia of Die na marmarata (Locu bida include 



t lint oocytes do not arise, ;is Wjdovsky liad assumed, directly from cells of terminal 61 i nent 

 of ovary without Intervening oogonial stage. A huh- thai germ cells of this form 



dial vox i from and wholly independent <>!' terminal Glamenl - or epil helium. -Well defined oogo- 

 nia, of indefinite number of cell general ions, arc demonstrated in domestic cat. Ob 

 lead to conclusion that primary genital cells of cat ("sex cells" of ■ r ei her 



become oogonia directly, or l>ecome indifferent epithelial cells which are then capable of b ■■■ i n- 

 ing oogonia. Shows that absolute genetic distinction of germ and follicle cells, ted 



by Rubaschkin, is not universal. — Work is regarded as qualified confirmation of Nussbaum'fl 

 theory of origin of germ cells. — A. Franklin Shull. 



3-1. Hall, Prescott F. Immigration restriction and world eugenics. Jour. Heredity 10: 

 125-127. Mar., 1919— See Bot. Absts. 3, Entry 1001. 



35. Harlaxd, S. C. The improvement of the yield of Sea Island cotton in the West Indies 

 by the isolation of pure strains. West Indian Bull. 17: 145-161. 1919. — Yield is dependent 

 on many factors, both morphological and physiological. Selection must aim to obtain 

 type with high yielding ability for certain environmental conditions. — Self fertilized seed 

 of individual plants was used for selection studies. Types were isolated with higher 

 mean values for number of ovules and seeds per loculus, number of loculi per boll, weight of 

 lint per 100 seeds and average seed size. Small-seeded strains were as vigorous as larger-seeded 

 sorts, but large seeds are desirable because of greater potential lint-bearing surface. One 

 strain, when compared with ordinary Sea Island cotton, gave increase in weight of lint per 

 boll, of 31 per cent. — H. K. Hayes. 



36. Harlaxd, S. C. The inheritance of immunity to leaf-blister mite (Eriophyes gossypii, 

 Banks) in cotton. West Indian Bull. 17 : 162-166. 1919. — Two varieties of cotton used. 

 Immune St. Vincent crossed with susceptible Southern Cross Upland gave intermediates in Fi 

 inclining toward susceptible parent. Segregation occurred in F 2 while in F 3 immune bred 

 true and non-immune again segregated. Author briefly summarizes his former breeding 

 investigations anent immunity to Eriophyes gossypii. — R. J. Garber. 



37. Hayes, H. K., and E. C. Stakman. Rust resistance in timothy. Jour. Ame \ Soc. 

 Agron. 11 : 67-70. 1919.— See Bot. Absts. 3, Entry 107. 



38. Heilborn, Otto. Zur Embryologie und Zytologie einiger Carex-Arten. [Embryology 

 and cytology of several species of Carex.] Svensk Bot. Tidskr. 12:212-220. 14 fig. 1918. 

 [Through review by C. J. Chamberlain. Bot. Gaz. 67: 448. May, 1919.] — Oogenesis and 

 spermatogenesis have been studied in several specie < of Carex, special attention being given 

 to chromosome numbers, which vary greatly in this genus. The gametophyte number- in 

 the forms investigated are as follows: Carex pilulifera S, C. ericetorum 16, C. digitata 24, 

 C. caryophylla and C. flava 32. Juel had already reported 52 for C. acuta, and Stout 37 for 

 C. aquatilis. C. pilulifera has the largest chromosomes, and in species with higher numbers 

 the chromosomes are correspondingly smaller. Attempts to cross the various species have 

 not yet proved successful, but the work is still in progress. See Bot. Absts. 1, Entry 1329.— 

 G. H. Shull. 



39. Herwerden, M. A. van. Over eenige nieuwe opvattingen in de celleer. [On several 

 new discoveries in cytology.] Genetica 1: 130-133. Mar., 1919. 



40. Humbert, J. G. Tomato diseases in Ohio. Ohio Agric. Exp. Sta. Bull. 321: 157-196. 

 12 fig. 1918.— See Bot, Absts. 2, Entry 767. 



