NOTES AND ABSTRACTS. 



357 



species of this interesting Burmanniaceous genus. The species is de- 

 scribed and a very full account is given of its anatomy, development, &c. 



The entire plant is glabrous and white ; the subepidermal cells are 

 full of coarse, septate fungus-mycelium. The main subterranean 

 structure is a root with root-cap, but is much reduced in vascular tissue. 

 Flower axis and roots arise endogenously from the main root or from 

 the base of the former. The ovules are anatropous, two-coated, and 

 a few-celled embryo is imbedded in a mass of endosperm. Insect 

 pollination seems necessary. The plates are particularly clear. 



G. F. S. E. 



Thistles, Canada. By H. R. Cox (U.S.A. Dep. Agr., Bull. 545, 

 1913, pp. 3-14; 6 figs.). — ^The Canada thistle [Cirsium arvense) can 

 iDe exterminated by repeatedly cutting off the tops. — 5. E. W. 



Thrips on Potato Foliage. By C. French (Jour. Dep. Agr. Victoria, 

 Dec. 1913, p. 730). — 35 up to 75 lb. of lime to 100 gallons of water 

 is highly recommended. — C. H. H. 



Tobacco Crop in Connecticut. By E. H. Jenkins (U.S.A. Exp. 

 ■Stn., Conn., Bull. 180, 1914, pp. 1-65 ,* 15 plates). — Experiments 

 were made to determine the effect of various fertilizers on the character 

 of the tobacco leaf. Sulphates exert a deleterious influence on the 

 burning quality of the leaf. A supply of nitrogen in the form of 

 castor pomace or cotton -seed meal improved the quality and increased 

 the quantity of the crop. If the tobacco plants are attacked by 

 root rot, the ground must be sterilized by superheated steam or 

 formaldehyde, the former by preference, before planting. Calico or 

 mosaic disease is easily transmitted by handling a healthy plant 

 after handling a calicoed one. A bibliography of works on wrapper 

 leaf tobacco is given. — S. E. W. 



Tobacco, Flue-cured. By E. H. Mathewson (U.S.A. Dep. 

 Agr., Bull. 16, 1913, pp. 1-36; 12 figs.). — ^The author discusses the 

 question of the rotation of crops and the use of fertiHzers for fiue- 

 cured tobacco. He also describes the cultivation and harvesting of 

 the crop. — S. E. W. 



Tomato, Influence of Crossing on Increasing the Yield of. 



By R. Welhngton (U.S.A. Exp. Stn., New York, Bull. 346, March 

 1912). — ^The effect of crossing a dwarf with a tall variety was to increase 

 the yield to a great extent, as compared with the amount of fruit 

 obtained from either parent. 



The cross gave an advantage of six tons from an acre, but the 

 gain was lost if the hybrid was self-fertiHzed and grown for three 

 generations. 



The author suggests that seed-growers could with advantage 

 raise Fi generation seed, as a higher price should be obtained for it. 



C. P. C. 



VOl>. XL, 2 B 



