No. 2, June, 1921] GENETICS 163 



nation and therefore incapable of accounting for phylogenesis. The author replies, however, 

 that no such inference can be drawn and that he has always warned against confusing the 

 catchword "Lamarckism" with the phenomena of somatic inheritance, the interpretation of 

 which can be placed upon a purely physiological basis. — M. A. Jull. 



1119. Shaffer, E. L. A comparative study of the chromosomes of Lachnosterna (Coleop- 

 tera). Biol. Bull. [Woods Hole] 38:83-103. 1920.— The diploid chromosome groups of 4 

 species of Lachnosterna (namely, delata, fusca, gracilis, and tristis), as well as Pelidnota 

 punctata and Cotalpa lanigera, show 20 chromosomes, 1 pair of which is composed of 2 unequal 

 elements (sex chromosomes). There are no essential differences in the form and arrange- 

 ment of the chromosomes in the species studied. Cyst formation in the testis begins by a 

 rapid division of a single primary spermatogonium, so that all the cells within any particular 

 cyst are the descendants of a single cell. The visible polarity of the cell seems to be estab- 

 lished at the time of cyst formation. The growth period of the spermatocytes is marked by 

 the appearance of delicate leptotene threads which are derived from the chromosomes of the 

 last spermatogonia! division; these threads become polarized and there is evidence that they 

 are arranged in pairs parasynaptically. There is a definite contraction phase. The sex 

 chromosomes persist through the entire growth period in the form of compact bodies, some- 

 times being contained within chromosomal vesicles. The unequal sex elements separate in 

 the 1st maturation division and divide equationally in the 2nd maturation division. In the 

 1st maturation division there are 5 atelomitic tetrads and 5 telomitic tetrads, the latter 

 including the sex pair. — Bertram G. Smith. 



1120. Slte, Maud. The relation of inbreeding to tumor production: studies in the inci- 

 dence and inheritability of spontaneous tumors in mice. Jour. Cancer Res. 1920. — Author 

 states that it is impossible to prove inheritability of any character without inbreeding. 

 Inbreeding reveals what is in a strain, nothing is "increased" or "intensified." Pedigrees 

 are given to show that inbreeding does not increase the incidence of cancer unless selection 

 of the cancer-bearing strains in a mixed population is made. — It is concluded that consistent 

 inbreeding eliminates any strain, and that inbreeding within a cancer strain speedily elimi- 

 nates the strain and instead of increasing cancer, as some have inferred, it eliminates cancer. 

 Hybridization increases cancer by increasing the output of cancer progeny. Cancer behaves 

 as a recessive. [See Bot. Absts. 7, Entry 1727.] — C, C. Little. 



1121. Stomps, Theo. J. tJber zwei Typen von Weissrandbunt bei Oenothera biennis L. 

 [On two types of white variegation in Oenothera biennis L.] Zeitschr. Indukt. Abstamm.- 

 u. Vererb. 22:261-274. 1920. — Author presents data bearing upon the heredity, in Oe. 

 biennis L., of 2 types of white variegation, as well as evidence for the appearance of these 

 types by mutation, their perpetuation by latent, semi-active, or active genes, and their 

 expression as phenomena of vegetative splitting. The works of Correns, Beyerinck, 

 Gregory, Baur, and Kxjster are discussed at length. In the 1st type of variegation vege- 

 tative mutation occurs in the periclinally dividing apical cell producing (1) green twigs and 

 (2) twigs with white-margined leaves. Selfed seed from green twigs give green, from varie- 

 gated twigs white, and the cross, variegated X green, a vegetative splitting into white and 

 green cell complexes, in the Fi. The latter are piebald variegated identical with types 

 which have arisen by mutation from pure green Oe. biennis X Oe. biennis cruciata. In either 

 case such plants are produced by the union of a "green" germ-cell with one mutated to 

 "white." The results of selfing green, nearly green, variegated, and strongly variegated 

 twigs of the piebald-variegated plants warrant the conclusion that each cell complex has 

 reached a definitive condition which may be transmitted to its offspring. The following types 

 fall in the piebald variegated class: Mirabilis jalapa albomaculata and Arabis pallida pseudo- 

 leucodermis, studied by Correns, Pelargonium zonale albomarginatum and Antirrhinum majus 

 albomaculatum, by Baur, and an albomaculata type of Primula sinensis reported by Gregory. 

 In all of these types the chlorophyll factor is carried over in a perlabile condition. In Mira- 

 bilis jalapa, reciprocal crosses, albomaculata X normal green, Correns and Baur report con- 



