12 GENETICS [BoT. Absts., Vol. X, 



78. Briggs, H. H. Hereditary congenital ptosis with report of 64 cases conforming to the 

 Mendelian rule of dominance. Trans. Amer. Ophthalmol. Soc. 16:255-276. 1918. — The study 

 is based on 128 persons in 6 generations, descendants of a single affected female and consti- 

 tuting a family of southern mountaineers. Of the entire number 64 were affected with ptosis 

 and 64 were normal; all the former had an aft'ected parent except 2, and in these cases the 

 evidence concerning the parent is not conclusive. The author discusses the Mendelian law 

 of inheritance and considers that his "cases conform to the Mendelian law of dominance." 

 The paper is illustrated with portraits and a pedigree chart; a review of the literature on the 

 subject and a bibliography of 45 numbers are added. — Howard J. Banker. 



79. Bkiggs, H. H. Hereditary congenital ptosis with report of 64 cases conforming to the 

 Mendelian rule of dominance. Amer. Jour. Ophthalmol. Ill, 2: 408-417. 1919. — The paper 

 published in Trans. Amer. Ophthalmol. Soc. 16: 255-276. 1918 (see preceding entry) is here 

 printed in "slightly abridged" form without portraits. — Howard J. Banker. 



80. Caron, von. Die Erfolge der Verwandtschafts- und Inzucht bei den Eldinger Weizen- 

 ziichtungen. [The results of consanguine breeding and of inbreeding in the Eldingen wheat 

 breeding.] Deutsch. Landw. Presse 1920: 390-391. 1920. — The author describes briefly his 

 methods in developing strains of wheat with high gluten content, immunity to rust, and other 

 desirable characters. He began with a wide cross and followed this with selection among 

 self-fertilized lines and later with crosses among these lines. — Sewall Wright. 



81. Carothers, E. Eleanor. Genetical behavior of heteromorphic homologous chro- 

 mosomes of Circotettix (Orthoptera). Jour. Morphol. 35: 457-483. 5 pi. 1921. — Both males 

 and females of Circotettix were collected from the wild; only nymphs of the females were used. 

 Eighteen matings were made. In 6 of these one or the other parent died, and in the remaining 

 12 only 8 produced offspring. After the eggs had been laid both parents were killed, and the 

 gonads were fixed and sectioned. Twenty-eight male offspring were studied cytologically. — 

 In C. verruculatus the spermatogonial complex consists of 21 chromosomes, 9 large atelomitic, 

 6 telomitic, and the other 6 may be either telomitic or atelomitic, but constant for an indi- 

 vidual. The complex for the female is similar except that there is an additional accessory which 

 gives constantly 10 large atelomitic chromosomes. In the spermatocyte 4 chromosomes and 

 the accessory are atelomitic, 3 are constantly telomitic, and 3 may vary from specimen to 

 specimen. The 28 males which were studied were the offspring of 5 crosses in which the 

 chromosomal complexes of the parents are known. No offspring varied in its chromosomal 

 constitution beyond the limits to be expected from a combination of the gametes of its parents. 

 These homologues have been actually identified in both parents and offspring. — Mary T. 

 Harman. 



82. CoRRENS, C. Versuche bei Pfianzen das Geschlechtsverhaltnis zu verschieben. 

 [Attempts to modify the sex ratio in plants.] Hereditas 2: 1-24. 5 fig. 1921. — The present 

 theory of the mechanism of sex determination is explained in detail and the evidence briefly 

 summarized. Examples of modified sex ratios in several species are pointed out. The paper 

 deals particularly with the author's experiments in the genus Melandrium. This is a dioecious 

 plant which has been found by various investigators to produce approximately 4-1 per cent 

 male and 56 per cent female plants. By applying pollen in different amounts it was possible 

 to modify the ratio even more. When an overabundance of pollen was used the number of 

 females in the progeny increased 12 per cent over that in the progeny from plants on which 

 but a small amount of pollen had been applied. The proportion of males to females was also 

 changed by cutting off the style soon after pollination and before all the pollen tubes had 

 reached the ovules. In 1 case the progeny of a plant so treated produced 69 per cent female 

 and 31 per cent male plants. Both of these experiments indicate that the female-producing 

 pollen grains have a more vigorouspollen tube or in some other way effect a more rapid fertili- 

 zation of the ovules. By careful drying it was possible to keep alive the pollen of Melandrium 

 for 120 days. When old pollen was applied the resulting progeny showed a decrease in the 

 percentage of female plants; this decrease became more pronounced with increasing age of the 



