AGRICULTUBAL BOTANY. 729 



Most cacti are found to have two divisions of tlie root system, an anclioring 

 and an absorbing system. In some cases flesliiness is developed, and in tlie 

 roots of opuntias tliis is a condition resulting directly from an abundant supply 

 of water. A sunllnr phenomenon was observitl in BiodUea cdpihita. 



Perennials with the generalized type of root system were found to have the 

 widest local distribution, while those with a pronounced development of the tap 

 root are limited in their distribution. 



The anatomy and some biological aspects of the ball moss, Willie I. 

 BiRGE {Bid. Univ. Texas, Sci. 8cr. No. 20, 1911, pp. 2'/, pis. 10). — A study was 

 made of the ball moss (Tillandsia recurvata) to determine some of its biological 

 aspects. 



From the anatomical as well as the morphological structure of the plant it is 

 claimed that it is epiphytic rather than parasitic. The holdfasts do not pene- 

 trate beyond the dead cortex of the bark, and there is a lack of organs for the 

 absorption and conduction of food, making it impossible for the plant to get 

 its nourishment through the roots, which mei'ely attach it to its substratum. 



An inquiry was made regarding the effect of this plant on the trees bearing 

 it, the common belief being that it often destroys trees by too much shading. 

 It appears that possibly some buds are smothered by the dense growth of the 

 moss on the young branches. Experiments in spraying with a 10 per cent 

 solution of kerosene were conducted, with the result that all the younger plants 

 were killed by the spraying. A somewhat stronger solution should be used for 

 the older plants. 



Investigations on the respiration of plants, W. Zaleski and A. Reinhard 

 (Biochem Ztschr., 35 {1911), Xo. 5-//, pp. 228-^J,5 ; ahs. in. Jovr. Chem. Soo. 

 [London], 100 {1911), No. 589, II, p. 1021).— Seeds, seedlings, and etiolated 

 leaves of peas, lupines, wheat, beans, and cucurbits, leaves of a begonia, and 

 buds of Populus sp. were ground in a mortar and the effect of the destruction of 

 their cells on respiration was determined. 



In some cases the respiration, as measured by the carbon dioxid output when 

 compared with that of living material, was increased after grinding, while in 

 others it was diminished. When sugar solutions fermented with zymin were 

 added to cultures containing pulverized wheat and pea seedlings, or where 

 yeast extract was employed, respiration was considerably accelerated. Quinin 

 had no effect on the respiration of pulverized or germinating pea seed. 



The influence of the partial suppression of the reserve material in seed on 

 the development of the plant, Delassus {Compt. Rend. Acad. Sci. [Paris], 

 153 {1911), No. 26, pp. Ili91f-l/i97). — Experiments are reported on beans, vetches, 

 and lupines in which portions of the reserve material were removed. Tlie seeds 

 were soaked in water for 24 hours, and from seed of different lots one-half of a 

 cotyledon, an entire cotyledon, and one and one-half cotyledons were removed, 

 after M'hich the seeds were planted in open soil. The germination, growth, 

 number and size of leaves, fresh and dry weight of plants, and period of flower- 

 ing and fruiting of the different lots were noted. 



In general it was found that the injury retarded the development of the 

 plants through the different stages of growth, and that the influence was almost 

 in direct proportion to the extent of the mutilation. An interesting observation 

 was also made, that the weaker vetch plants which were grown from mutilated 

 seeds were much more injured by fungus attack than were the plants from 

 uninjured seed. 



On protein formation in ripening seeds, E. Schulze {Hoppe-Seuler's ZtscJir. 

 Physiol. Chem., 11 {1911), No. 1, pp. 31-Ji8). — This is a continuation of work 

 done by the author in connection with E. Winterstein (E. S. R., 24, p. 531) and 



