No. 3, April, 1921] GENETICS 255 



lividus.] Arch. Zool. Exp. Notes et Rev. 57:28-31. 1 fig. 1918.— Specimen of this sea 

 urchin had three normal testes, one atrophied testis, and large mixed gland. Functional 

 eggs and spermatozoa from mixed gland united in self-fertilization, and from the fertilized 

 eggs normal plutei developed. Eggs of this hermaphrodite also united normally with sperma- 

 tozoa of normal males, and its spermatozoa fertilized eggs of normal females. Atrophied 

 testis contained parasite, but there was nothing to indicate that hermaphroditism depended 

 on parasitism. — A. Franklin Shull. 



1768. HiLDEN, K. Anthropologische Untersuchungen iiber die Eingeborenen des russis- 

 chen Altai. [Anthropological investigations on the natives of the Russian Altai.] 137 p. Hel- 

 singfors, 1920. 



1769. HoGBEN, Lancelot T. Studies on synapsis II. Parallel conjugation and the pro- 

 phase complex in Periplaneta with special reference to the premeiotic telophase. Proc. Roy. 

 Soc. London 91: 305-329. S pi. Aug. 7, 1920.— Author studied spermatogenesis and oogene- 

 sis in Periplaneta (cockroach); first account of the latter. Author does not observe anaphase 

 chromosomes of the late oogonia to be split, in contrast to this condition observed by Miss 

 DiGBY in the premeiotic anaphase chromosomes of Osmunda. There are thirty-two autosomes 

 and two accessory chromosomes in the female, one accessory in the male. Parasynapsis 

 occurs in both sexes; in the female the accessories and autosomes do not behave differently. 

 He observes no twisting filaments in the zygotene stage and believes that the union of the 

 constituent halves of this stage is sufficiently intimate to allow the possibility of crossing 

 over but not by such means as are postulated by the chiasmatype theory. In oogenesis segre- 

 gation of homologous chromosomes appears to take place in the first maturation division, 

 but has no data to indicate that this occurs in spermatogenesis. — C. L. Parmenter. 



1770. Hovasse, R. Le nombre des chromosomes chez les tetards parthenogenetique de 

 grenouille. [The nimiber of chromosomes in parthenogenetic tadpoles of the frog.] Compt. 

 Rend. Acad. Sci. Paris 170: 1211-1216. May, 1920.— The author has determined the approxi- 

 mate number of chromosomes in the cells of parthenogenetic tadpoles and gastrulae of Rana 

 temporaria. In two tadpoles, aged 50 and 80 days, the number is diploid (24-27) which he 

 interprets as being produced by regulation (Delage), a doubling of the chromosome number 

 very early, perhaps at the beginning of segmentation. In two gastrulae, 8 days old, the num- 

 ber varies from approximately 15 to 28 and the size of the nuclei varies accordingly from 5 

 to 16 microns in diameter. These numbers he interprets as due to regulation in only a part 

 of the cells. The number of chromosomes in the cells of seven sickly tadpoles, aged 16 days 

 and less, is haploid, and the nuclei are about half normal size. These conditions are cited 

 as very comparable to those obtained by Dries ch in parthenogenetic sea-urchin embryos. 

 Delage adds a note emphasizing these data as confirming his regulation theory. — C. L. 

 Parmenter. 



1771. Howe, Lucien. The relation of hereditary eye defects to genetics and eugenics. 

 Jour. Heredity 10: 379-382. Nov., 1919.— Pointing out the attitude which the ophthalmolo- 

 gist must take in regard to hereditary blindness and showing that sterilization or sequestra- 

 tion of carriers of the defect is legal in some states. — /. H. Beaumont. 



1772. Hume, A. N. A system for breeding corn or gregarious animals. Jour. Heredity 

 11: 191-192. April, 1920. — A brief description of a plan for breeding and selection which is 

 fully outlined in South Dakota Experiment Station Bulletin 186 (Bot. Absts. 5, Entry 1532). 

 The plan consists in introducing ears from outside the breeding-plot into the even-numbered 

 detasseled rows, which gives opportunity for testing the yielding power of such introduc- 

 tions before permitting them to contaminate the other "blood lines." The system is especi- 

 ally applicable to poultry where 4 or more pens are used and accurate egg-laying records are 

 kept. — J. H. Beaumont. 



1773. Jablonski, Walter. tJber Albinismus des Auges im Zusammenhang mit den 

 Vererbungsregeln. [On albinism of the eye in connection with inheritance laws.] Deutsch. 

 Med. Wochenschr. 46: 708-711. 1920. 



