No. 1, May, 1921] GENETICS 43 



278. Kathariner, L. Die Entwicklungsgeschichte der digenetischen Trematoden und 

 die Kontinuitat des Keimplasmas. [The ontogeny of the digenetic trematodes and the con- 

 tinuity of the germplasm.] Zool. Anzeig. 51: 220-223. 1920. — Reiteration of view that sporo- 

 cyst, redia, and cercaria are not individuals of distinct generations, but that all have been 

 produced from cleavage cells of same fertilized egg. Life cycle does not therefore involve 

 parthenogenesis nor true paedogenesis. — A. Franklin Shull. 



279. KoHN, Alfred. Der Bauplan der Keimdriisen. [The structural plan of germ- 

 glands.] Arch. Entwicklungsmech. 47:95-118. 7 fig. 1920. 



280. KoTOWSKi, Feliks. Zmiennose i Korrelacye w "czystej linii" pszenicy. Tr. vulgare 

 Ostaka biala dublanska. [Correlation and variability in a pure line of wheat.] Polinusch: 

 Tygodnika Rolniczy, Krakau, 1919. — Biometrical studies on 387 wheat plants. Coefficient 

 of variability ranged from 7.06 per cent for length of stem to 43.07 per cent for weight of 

 upper 20 cm. of stem in distributions that were found to be according to Quetelet's law. 

 Correlation between stem length and weight of ear was only 0.20 ± 0.094 and author attributes 

 little breeding value to stem length. Selection made with respect to weight of lower part of 

 stem considered good. Correlation between ear weight and weight of lowest 20 cm. of stem 

 was 0.75 ± 0.043. Author does not ignore value of direct field selection in respect to non- 

 lodging characteristic. [From anonymous German review in Zeitschr. Pfianzenziicht. 7: 

 333-334. Nov., 1920.]— Ja?nes P. Kelly. 



281. Krafka, Joseph, Jr. Environmental factors other than temperature affecting facet 

 number in the bar-eyed mutant of Drosophila. Jour. Gen. Physiol. 3: 207-210. 1920.— 

 Following the author's previous work with temperature in producing a change in facet num- 

 ber of the ultra-bar mutant of Drosophila melanogasier various tests were made to deter- 

 mine the effect of other environmental factors. Certain consistent and apparently signifi- 

 cant changes in facet number were obtained but they were of slight amount. Provided a 

 consistent procedure is followed and plenty of moist food available, temperature seems to 

 be the only environmental factor which need be considered in interpreting breeding data in 

 Drosophila. — H. H. Plough. 



282. Krafka, Joseph, Jr. The post-embryonic development of the compound eye of 

 Drosophila melanogaster. [Abstract.] Anat. Rec. 20: 231. 1921. — A histological study has 

 been made of the development of the compound ej^e of Drosophila melanogaster Meig. The 

 embryoblasts are present at the time of hatching, although the ommatidia are not completely 

 metamorphosed until the late pupal period. The segmented condition of the optic ganglion, 

 before definitive visual structures appear, suggests that the formation of the latter may be 

 under the control of the nervous system. A marked reduction in the size of the optic ganglion 

 in the bar-eyed mutant shows that the hereditary factor involves more than the facet number. 

 — Joseph Krafka, Jr. 



283. KRtJGER, Paul. Studien an Cirripedien. [Studies on Cirripedes.] Zeitschr. 

 Indukt. Abstamm.- u. Vererb. 24: 105-108. 13 fig. 1920. 



284. KtJsTER, E. Beitrage zur Kenntnis der panaschierten Laubgeholze. [Variegation in 

 broad-leafed trees.] Mitteil. Deutsch. Dendrolog. Ges. 28: 85-88. 8 fig. 1919. 



285. Lancefield, D. E. Two sex-linked lethals of simultaneous appearance in Droso- 

 phila obscura. Proc. Soc. Exp. Biol. Med. 17:56-57. 1919. — Genetic data in Drosophila 

 obscura indicate the simultaneous appearance of 2 sex-linked lethal factors in the same 

 culture. Breeding tests show that these 2 factors are apparently" located at opposite ends 

 of a sex chromosome longer than that of Drosophila melanogaster. — H. H. Plough. 



286. Laughlin, Harry H. Illustrating the structure and mathematics of the human germ- 

 plasm. Jour. Heredity 11: 185-189. 1 fig. 1920. — A figure and description of "an abacus" 



