No. 1, Jolt, 1920] GENETICS 95 



(1) I'd, cilop< i lapponaria 



(2) !'<>( cilopxis rtirht las 



[mmediate phylogenetic source of .V. zonaria. I', lap- 

 ponaria was probably derived from /. icia hirtaria. 

 Females normally wingless. 



(3) Poecilopsis pomonaria, 51 chromosomes I More recently derived from L. Atrtono. 



(4) Poecilopsis Isabellas, 52 chromosomes [ Females wingli 



(5) Lyraa Mrtana (Stem-form of the group. 9 winged. 11 chromosome 



The cxcci. i imis are 1 1) thai in the cross involving o* P. <■" hela a few intersexes occur in I 

 brood of male offspring. -(2) When any <>f these dV (excepl /,. hirtaria) comes from in- 

 bred stock, a few female offspring arc produced with the males, e.g., P. /<"» ' tve 



7 9 9 , 71 dV; 3 9 9 , G2 dV. (3) A half-size ? was obtained in addil ion to males from 



iria 9 X (P. pomonaria o" X isa6< /'-"• 9).— The d" N. zonaria, on the contrary, in corre- 

 sponding reciprocal crosses gives normal sex ratios, a slight excess of 9 9 being usual. An- 

 other 9 Nyssia, N. graecaria 9 X /,. hirtaria cf also produces only males, and the closely 

 allied North American P. rachelae 9 X L. hirtaria d" gives only males and intersexes. — 



irpretal ion: The female being the heterozygous sex in Lepidoptera, both male and fernale- 

 producing eggs are formed by 9 N. zonaria, the phylogenetically youngest member of thi3 

 group of species. These eggs arc presumably (not demonstrably) distinguished by an X or a 

 Y chromosome. The superior potency, or (quasi-electric) sex potential, of the sex factors or 



•inosomes, X', X', of the various sexually homozygous males of these "phylogenetically 

 older" species forces the resulting X'Y zygotes (50 per cent) out of femaleness into male- 

 in - -, except in those cases in which the potential of the sex factor of the male was lowered 

 by previous inbreeding, whereby a few females remain untransformed, or, as in the cross 

 involving P. rachelae d 1 , a few intersexes occur with the males. In the interesting case of 

 the 9 of half -size, supplementary to the male offspring from N. zonaria 9 X (P. isabellae 9 

 X P. pomonaria <?) d\ the male parent was extraordinarily large and vigorous. The pygmy 

 daughter is supposed to be the result of a dislocation of the XY chromosomes in the first cleav- 

 age so that, for example, instead of dividing and being distributed to each pole, one passes 

 !irided to each daughter nucleus. If the resulting XO cell is non-viable, the other (YO) 

 of female tendencies alone controls development of the supposed half embryo, regenerating 

 a diminutive whole. Another method of chromosomal dislocation with similar outcome is 

 mentioned. — The extraordinarily large proportion of males (190:14) from L. hirtaria 9 of 

 Scotch origin X P. pomonaria d 1 , whereas this cross made with a 9 hirtaria of English stock 

 gives a normal ratio (e.g. 86 0*0* ; 75 9 9 ) is ascribed to a physiological "racial variation of 

 the powers of the sex determiners," and inadvertently compared to cases like zonaria 9 X 

 hirtaria d 1 giving only males. Intersexes only are the product of the 9 Fi hybrid (P. pomonaria 



9 X L. hirtaria d 1 ) X P. pomonaria d\ Genitalia of seven are described, and figures of the 

 wings shown. — Interpretation: No reduction division is assumed to occur in gametogenesis 

 of the hybrid mother. Her gametes thus carry X'Y (X' from the hirtaria d 1 ) and those of 

 the pomonaria d* bring X, forming zygote XX'Y, essentially 9 but maladjusted by the pres- 

 ence of X' and other supernumerary chromosomes. Chromosomal dislocations in mitosis 

 at different stages of cleavage are assumed to explain the individual differences in sexual and 

 somatic characters of the various fundamentally female gynandromorphs. — Finally the geni- 

 talia of an intersex (chiefly 9) from P. lapponaria 9 X P. pomonaria d\ which occurred in 

 a brood with normal sex ratio, are described. — J. H. Gerould. 



59S. Hayes, H. K., and R. J. Garber. Breeding small grains in Minnesota. I. Tech- 

 nic and results with wheat and oats. Univ. Minnesota Agric. Exp. Sta. Bull. 182: 1-44. 



10 fig. Mar., 1919. — Methods of technique, together with the history as practiced at the Min- 

 nesota Experiment Station, are outlined, for new introductions, straight selections and crosses. 

 At ?>Iinncsota, the centgener plan of breeding, or straight selection, was apparently practiced 

 from 1908 to 1914. New introductions were prolifically made from 1915 to 1917. Both spring 

 and winter wheats are treated, giving varieties, methods and accomplishments. There is 

 much tabular matter on the behavior of winter wheat at Grand Rapids and Waseca and aver- 

 ages for all stations. For spring wheat, results are given for University Farm, Crookston, 



