No. 1, November, 1921J GENETICS 17 



95. Haviland, Maud D. Preliminary note on antennal variation in an Aphis (Myzus 

 ribis Linn.)- Proc. Cambridge Phil. Soc. 20: 3.5-44. 1920. — The author reports that within 

 asinglecloneof .l/yzj<srf6is ratios of certain antennallengtlis to head breadth decreased with 

 feeding on red-blistered leaves and increased with feeding on green unblistered leaves. Trans- 

 ference of red-fed individuals to green food indicated persistence of the effects of red food for 

 2 or 3 generations. — /. P. Kclltj. 



96. Hein, S. a. Auendsen. Studies on variation in the meal-worm, Tenebrio molitor. 

 I. Biological and genetical notes on Tenebrio molitor. Jour. Genetics 10: 227-204. 16 fig. 

 1920. — Tenebrio molitor is a common beetle belonging to the series Ileteromera, in which the 

 1st and 2nd pairs of legs have 5 joints to the toes but the 3rd pair only 4. As there are over 

 15,000 species of Heteromera, this character may be considered to have remained fixed for 

 millions of years. Nevertheless, on examining 35,247 individuals of T. molitor, no less than 

 60 were found with 5 joints in the posterior toes. Breeding from these gave only negative 

 results, the character apparently being not inherited; but on the other hand, when beetles, 

 with fewer joints in the toes than normal, were bred together, the character was found to be 

 inherited. Variations in the color of the eyes were found; the normal eye is intense black. 

 Cream-white eyes show sex-limited descent; red eyes are apparently not sex-limited. The 

 larvae show variations in color and structure, which w^ere studied. Numerous details are 

 given concerning the life-history and characters of the species. — T. D. A. Cockerell. 



97. Jackson, Hartley H. T. A hybrid deer of the Fa generation. Jour. Mammalogy 2: 

 140-143. 1 pi., 1 fig. 1921. — On the eastern slopes of the Cascade Mountains in the State of 

 Washington there is a limited area in which the ranges of the mule deer, Odocoileus hemionus 

 hemionus, and the Columbian black-tailed deer, O. columbianus columbianus, overlap. In the 

 wild state these 2 species have been known to hybridize, but the F2 individual reported 

 was bred in captivity. The Fi sire of this specimen (now No. 223,685 U. S. National Museum, 

 Biological Survey Collection) was sired by a full-blooded mule deer out of a black-tailed doe. 

 The Fi dam was sired by a full-blooded black-tail buck out of a mule doe. Each of these 

 individuals was bom and raised in captivity. Nevertheless, there were no data available on 

 the traits of the parental generation or the Fi parents, so a comparison with the 2 pure species 

 in general was all that was possible. The author draws 2 conclusions: (1) The Fi hybrids are 

 fertile among themselves despite widespread recognition of the parents as distinct species; 

 (2) certain unit characters are transmitted to the offspring in addition to characters that are 

 apparently intermediate in nature. The Fo individual was essentially a mule deer in shape 

 and size of horn, in shape of the post-orbital region of the skull, in the size of the metatarsal 

 glands, and in the general body size. It showed the black-tailed character of 0. columbianus 

 columbianus, however. — Edward N. Wentuorth. 



98. Jeffrey, E. C, The geographical distribution of hybrids. Science 53 : 556. 1921. — 

 The author objects to criticisms directed against Brainerd and Peitersen (see Bot. Absts. 

 8, Entry 233) for classifying as hybrids blackberry (Rubus) forms which occur outside the 

 range of the supposed parents. Instances are cited from Kerner in support of the con- 

 tention "that absence of one or both parent species of a supposed hybrid in a given region is 

 no valid argument against the hybrid origin of such an intermediate form." — R. E. Clausen. 



99. Jones, L. R., J. C. Walker, and W. B. Tisdalb. Fusarium resistant cabbage. 

 Wisconsin Agric. Exp. Sta. Res. Bull. 48. 34 p., 10 fig. 1920. — Cabbage yellows, widespread 

 in the eastern U. S. A., is caused by the fungus Fusarium conglutinans Wollenw. The fungus 

 penetrates the root hairs, pushing through the cortical tissues until it reaches the vascular 

 system. This leads to the death of the vascular tissues followed by a slow yellowing of the 

 aerial parts. Soil remains infected almost indefinitely. The destructiveness of the disease 

 depends on seasonal conditions as aggressive host invasion occurs only at relatively high tem- 

 peratures, 17°C. and above. — As a result of careful selection experiments the conclusion was 

 reached that resistance is due to heritable differences (multiple factors) and that by selection 

 of resistant heads from "sick" soil a Fusarium-iesistsint strain may be secured. Disease 



