May, 1920] GENETICS 213 



150_'. ScHAFPNBR, John H. Complete reversal of sex in hemp. Science 50 : .'il 1-312. 

 Sept. 26, 1919. Hemp grown in winter in greenhouse matures very early, never more than a 

 few inches high. The plants are decidedly dimorphic, carpelled and staminate. The two 

 types are briefly described. Some staminate plants later produce intermediate structures, 

 part ovulary and part stamen. These intermediate plants usually become purely staminate 

 toward the end of tlie season. Carpelled plants are usually purely carpellate at first but 

 may later develop stamens in some Mowers. Most of the carpellate planl v this reversal 



of sex only on attaining advanced age. There is much variation in the age at which the 

 change is produced, and in the degree of perfection of stamens and anthers. In one plot 

 over 50 per cent of the plants that produced only female characters at first were finally pro- 

 ducing only typical male characters. "Female heredity is at first active and male heredity 

 latent, and finally male heredity is active and female heredity is latent." — Geo. II . Skull. 



1503. Schaffner, John H. Unusual dichotomous branching in Vernonia. Ohio Jour. 

 Sci. 19: 487-490. 1919— See Bot. Absts. 3, Entry 1574. 



1504. Schultz, Waltiier. Versteckte Erbfaktoren der Albinos fur Farbung beim Rus- 

 senkaninchen im Soma dargestellt und rein somatisch zur Wirkung gebracht. [Hereditary 

 color factors hidden in albino Russian hares, demonstrated in the soma, and purely somatically 

 activated.] Zeitschr. indukt.Abstamm. Vererb. 20:27-40. 9fig. Sept., 1918. — Hybridization has 

 demonstrated that Himalayan (Russian) albino and true albinos may carry latent and trans- 

 mit all the color and pattern factors which a colored rabbit carries, except the color factor 

 itself. Existence of these latent factors in some may be directly demonstrated by experi- 

 ment. In Himalayan, factors for self color and black appear activated when any part of 

 the body is depilated and new hair is grown subject to the external stimuli, temperature and 

 heat. Black hair may be grown even on belly (protected region difficult to influence) by 

 depilating and keeping animal in light room at approximately freezing temperature. Depil- 

 ated areas in colored rabbits and true albinos regenerate colored and white hair respectively, 

 but in the Himalayan such depilated areas grow black hair except at the border of this depil- 

 ated area where border hairs protect bare skin. When Himalayan was kept very warm, the 

 entire depilated area regenerated only white hair. Author believes this demonstrates differ- 

 ence between C, color factor, and Ci, factor for Himalayan condition, and c the factor for 

 complete albinism.— In true albino, various latent colors and color patterns were similarly 

 activated. New characters such as dapple, zebra-like markings, and heel-spot appeared. 

 Author believes these new characters predict possibility of germinal mutation in same direc- 

 tion at some future time. — /. A. Detlefsen. 



1505. Seiler, J. Researches on the sex-chromosomes of Psychidae (Lepidoptera). Biol. 

 Bull. 36: 399-404. 1 pi., 1 Jig. June, 1919. — In Talceporia tubulosa Retz., first oocyte division 

 shows 30 chromosomes, one of which fails to divide. Daughter plates show 29 or 30 chromo- 

 somes. In 134 cases the odd element passed outward, in 89, inward. This gives an expec- 

 tation of 1.5 females to 1 male. First and second spermatocyte divisions show 30 chromo- 

 somes. 30 embryos showed 59 chromosomes and 25 showed 60. Sex ratio as determined by 

 chromosome counts from embryos from Tornow material exactly agreed wdth distribution of 

 X element. Four embryos, possibly parthenogenetic, showed 58 chromosomes and two divi- 

 sions of first oocyte showed 29 passing to each pole. Fumea casta Pall, has 31 chromosomes 

 in first oocyte. Daughter plates show 31 or 30 chromosomes. Embryos have 61 or 62. — 

 B. Wolf, Jr. 



1506. Siemens, H. W. [Rev. of : Pribram, Dr. Hugo. Uber die Vererbung der diabetis- 

 chen Konstitution. (On the inheritance of the diabetic constitution.) Zentralbl. innere Med. 

 36: 1915.] Zeitschr. indukt. Abstamm. Vererb. 20: 158. Jan., 1919. 



1507. Siemens, H. W. [Rev. of : Rudin, Prof. Dr. Ernst. Studien iiber Vererbung und 

 Entstehung geistiger Storungen. I. Zur Vererbung und Neuentstehung der Dementia praecox. 

 (Studies on inheritance and origin of mental disturbances. I. On the inheritance and new 

 origin of dementia praecox.) vi + 172 p. Julius Springer: Berlin, 1916.] Zeitschr. indukt. 

 Abstamm. Vererb. 20: 157-158. Jan., 1919. 



