64 Floristik etc. — Angewandte Botanik. — Personalnachrichten. 



't5 



Swingle, W. T., Microcitrus, a new genus ofAustralian ci- 

 trous fruits. (Journ. Washington Acad. Acad. Sei. VI. p. 569 — 578. 

 f. 1—4. Oct. 4, 1915.) 



Contains as new: Microcitrus australasica {Citrus australasica 

 F. Mull.), M. australasica sangimiea (C. australasica sanguinea Bail.), 

 M. Garrowayi (C. Garrowayi Bail.), M. australis (C. australis Planch.), 

 and M. inodora (C. inodorus Bail.). Trelease. 



Townsend, C. O., Single-germ beetseed. (Journ. of Heredity. 

 VI. p. 351—354. 1915.)^ 



The writer's goal was the production of a strain of sugar beets 

 which yielded onl}^ one-germ seeds. More than 95 per cent, of the 

 beet seed of commerce is composed of multiple germ seedballs, the 

 germs of which are so closely melded together by nature that they 

 cannot by any known means be separated without injury to the 

 germ. The number of germs produced normally as Single germs 

 does not exceed 1 per cent, of the total number of germs, The 

 principal value of a strain, which yields only one-germ seeds, lies 

 in the economy of labor it would make possible. Thinning, the most 

 expensive and laborious Single Operation in sugar beet growing, 

 costs approximatel}^ 3.000.000 doUars annually for the entire beet 

 acreage in the United States. The only way to avoid this condition 

 and to eliminate the expense and labor of thinning beets is to have 

 all single-germ seeds. 



Fifty plants, showing the highest number of Single germs, as 

 indicated in the bud stage, were selected, trimmed (all flower 

 Clusters removed) and isolated as thoroughly as possible. Though 

 subsequent improvements have shown that in spite of all these 

 pecautions it was possible for unfavorable crosses to have been 

 made by minute insects, the writers results indicate that he was 

 in a measure successful in producing the pollination desired. The 

 percentage of Single germs of the fifty isolated plants was not 

 determined, but was somewhat above 25yo' In the second generation 

 the number of single-germ seeds was upwards of 50 per cent on 

 the best plant and in the third generation it was about 75 per cent. 

 Individual plants in a few cases show a somewhat higher percentage 

 than this. Continuing along these lines, it is fair to assume that it 

 is only a matter of time when a plant bearing only single-germ 

 seeds will be produced. A reasonable amount of care on the part 

 of the beet seed growers will then make the production of single- 

 germ beet seed commercially practicable. M. J. Sirks (Haarlem). 



Personalnaehriehten. 



Ernannt: Dr. Hugo Fischer zum Vorsteher-Stellvertreter am 

 Kaiser Wilhelm-Institut zu Bromberg, Abt. für Agrikulturchemie, 

 Bakteriologie und Saatzucht und hat die Leitung des bakteriologi- 

 schen Laboratoriums daselbst übernommen. 



Verstorben am 24. November in Strassburg Prof. dr. 

 Hermann Graf zu Solms-Laubach. 



Ausgegeben: 18 Januar 1016. 



Verlag von Gustav Fischer in Jena. 

 Bucbdruckerei A. W. S 1.1 1. hoff in Leiden. 



