No. 3, January, 1922] GENETICS 159 



210-211. 1921 (see Bot. Absts. 8, Entry 353). (3) Muller, H. J., and E. Altenburg. A 

 study of the character and mode of origin of eighteen mutations in the X-chromosomes of Droso- 

 phila. Auat. Roc. 20: 213. 1021 (sec Bot. Absts. 8, Entry 30G). (4) Buidues, Calvin B. 

 Vermilion-deficiency. Jour. Gen. Physiol. 1: 615-656. 1919 (see Bot. Absts. 3, Entry 981). 

 (5) Blakeslee, Albert F., John Belling, and M. E. Farnham. Chromosomal duplication 

 and Mendelian phenomena in Datura mutants. Science 52: 3SS-.390. 1920 (see Bot. Absts. 

 7, Entry SoS). (tj) Mulleu, H. J. Genetic variability, twin hybrids and constant hybrids, in 

 a case of balanced lethal factors. Genetics 3: 433-499. 1 fig. 1918 (see Bot. Absts. 2, Entry 

 257). (7) Vries, H. de Phylogenetische und gruppenweise Artbildung. (Phylogenetic and 

 group-wise species formation.) Flora 11, 12 (Festschr. E. Stahl) : 208-22G. 1918 (see Bot. 

 Absts. 5, Entry 349).] Bot. Gaz. 72 : 178-182. 1921. 



1044. Cunningham, C. C. Study of the relation of the length of kernel to the yield of 

 corn (Zea mays indentata). Jour. Agric. Res. 21 : 427^38. PL 80-87, 1 fug. 1921.— Corn from 

 ears with short, smooth, or dimpled kernels, from ears with kernels of maximum length with 

 chaffy crowns, and from ears with kernels of medium length and wrinkled dented, were 

 planted. Seed was continuously selected, smooth, rough, and medium ears being chosen 

 each season from the progeny of smooth, rough, and medium ears, respectiveh'. The 3 types 

 made respective 4-year average yields of 36.5, 35.5, and 34.8 bushels per acre. — Continuous 

 selection of smooth and rather short kernels for 4 generations increased the average length of 

 ears, slightly decreased the weight, and decreased the circumference, number of rows per 

 ear, length of kernel, and percentage of shelled grain; while continuous selection of rough and 

 rather long kernels decreased the average length of ear and increased the circumference, 

 but had no significant effect on the weight of ears, number of rows per ear, length of kernel, 

 or percentage of grain. — H. M. Steece. 



1045. Czaja, a. Th. [German Rev. of: Steil, W. N. A study of apogamy in Nephrodium 

 hirtipesHk. Ann. Botany 33: 109-132. 3 pi. 1919 (see Bot. Absts. 2, Entry 738).] Zeitschr. 

 Bot. 13 : 599-601. 1921.— [See also Bot. Absts. 4, Entry 985.] 



1046. Darrow, Geo. M. Are our raspberries derived from American or European species? 

 Jour. Heredity 11 : 179-184. 4 fig- 1920. — Because of the relative hardiness of the cultivated 

 red raspberries in America as compared with the European species, pomologists have always 

 considered them as representative of the pure native species Rubus sirigosus. The author 

 disagrees because of the observed differences in the cultivated varieties from both native and 

 European species. For authority on the botanical characters of the pure native and the foreign 

 species such names are cited as Rydberg, Card, and Foche. Tables are included with brief 

 descriptive terms of 10 varieties of R. strigosus, 7 of R. strigosus X it!, occidentalis, 16 of R. 

 Idaeus, 9 of R. Idaeus X R. strigosus, and 3 of R. Idaeus X R. occidentalis. The derivation of 

 the varieties mentioned in the tables was obtained (1) by an inspection of herbarium material 

 supplemented where possible by observations of the varieties in the field; (2) by a study of the 

 historj' of the variety in question. The author admits that some of these derivations may 

 be questionable and for final analysis must be submitted to the more rigid tests of the plant 

 breeder. — L. R. Detjen. 



1047. Dykes, W. R. Iris acutikor. (Iris acutiloba and I. Korolkowi.) Gard. Chron. 70: 

 5. 1921. — The author describes and figures a hybrid produced from I. acutiloba jiollinated 

 by I. Korolkowi, the hybrid showing characters of both parents; those that survived were both 

 sturdier and more floriferous than either parent. — J. Marion Skull. 



1048. East, E. M., and D. F. Jones. Round Tip tobacco. A plant ''made to order.'' 

 Jour. Heredity 12:51-56. Fig. 1-5. 1921. — Apopular description is presented of the desirable 

 qualities of cigar wrapper leaf, the origin of the Round Tip type, together with the advantages 

 of this type over others grov/n in the Connecticut Valley. Round Tip is the result of a 

 cross between the Sumatra and Broadleaf -varieties, and has been grown commerically suffi- 

 ciently to indicate that it possesses great possibilities from the farmer's standpoint if the trade 

 will accept the type on its own merits. — •/. Johnson. 



