lf>20] FIELD CROPS. 133 



I'urtlior stiulics on synihiosis bt'twcoii Ardisia ci'ispa and its bartoria. — 

 II, TIio plants without bacteria, II. Mikiie {.Jdhrb. Wihh. Hot. [I'riHiJsheini], 

 58 (1017), \o. J, pp. 29-65, figx. iO).— This contribution, in contrast to those 

 previously noted (E. S. R., 28, p. 35; 29, p. 30), deals with .1. crixpa as free from 

 bacteria. Re.spectinfj; the relations between the synibionLs, it is rejrarded as 

 safe to say only that these relations jire very intimate, involving under natural 

 conditions the normal development of the host. 



Venation and senescence of polyenibryonic citrus plants, M. It. Ensign 

 (.t»irr. Jour. Hot., 6 (li)W), No. 8, pp. 311-32'J, figs. 6).— It is stated that 43.18 

 I>er cent of the seeds of Citrus grandis produce polyembryonic shoots. An 

 acctmnt is given of the apparent relations between leaf venation and other 

 features of C. grandis. 



Studies concerning; the evolutionary status of polycotyledony, J. T. 

 r.rcHiroLz {Aiiier. Jour. Bot., 6 (IDJD), No. 3, pp. 106-119. figs. 2«).— The autlior 

 has studied the ontogeny of the cotyledons in the various livinj; conifers for 

 modern evolutionary tendencies in hope of obtaining a criterion to determine the 

 actual present direction of this particular evolution of the cotyledons. 



The results of this study show that in a number of conifers fusions of the 

 cotyledons occur during their embryonic development. No evidences of split- 

 ting cotyledons were found in any species. Cotyledonary fusion has given rise 

 to cotyledonary tubes in some species. Polycotyledony is thought to have been 

 the primitive condition. The facts deduced are considered to show that the 

 primitive gynmosperm embryo had numerous cotyledons imperfectly cyclic and 

 variable in number, probably derived from spirally arranged leaves that be- 

 came cyclic in the cotyledonary node. Dicotyledony was attained either by a 

 general fusion of cotyledons in two gi-oups or by an extremely bilabiate develop- 

 ment of a cotyledonary tube ; monocotyledony resulted from a cotyleilonary 

 tube becoming unilabiate. 



Flax blooms, T. T.\mmes {Rec. Trav. Bot. N6erland., 15 (1918), No. 2, pp. 

 185-221, figs. 21). — This study is concerned with structures and relations as 

 note<l in flax blooms in connection with po.ssibilities and probabilities regard- 

 ing fertilizaton. 



FIELD CROPS. 



Farm crop investigations, .T. E. Mktzc.er et at.. [Marghind fitn. Rpf. 1919, 

 pp. A'.A7/-A'A']7). — Ten different projects, including work' with corn, cowpeas, 

 soy beans, tobacco, oats, wheat, crop rotations, and forage, green manure, and 

 cover cro])s are described, and some of the results secured are brielly noted. 



Of 16 varieties of corn tested the past year, in 5 diff^-ent placi's in the 

 State, Boone County White, Johnson County White, Excelsior, Thomas, and 

 Funk Yellow Dent were araong those giving the best results. The highest 

 yield of silage was secured from Cocke Prolific, Johnson County White, Boone 

 County White, and Excelsior. The results obtained w'ith the different vari»'ties 

 varied greatly. In general two plants per hill gave larger yields of shelled coru, 

 but less stover, than was secured from three plants per hill. 



In tests with cowpeas, begun in 1J)09, M'onderful, Whippoorwill, droit, New 

 Era, Gray Crowder, and Black are recorded as having given the best results. 

 The work with soy beans, undertaken in 1910, showed that Virgliua, Wil.son, 

 Cloud, Ito San, Peking, Edna, Medium Yellow, and Mammoth Yellow were 

 the most successful varieties. 



Exi)erinienls conducted since 191.^ <m the production of sweet corn seed 

 indicated that liome-grown seed produced larger ijlants and gave higher 



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