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Haaren High School exhibited cactus gardens. 



George Washington High School exhibited twigs of trees and 

 microscopic preparations. 



A number of exhibits were set up by Columbia University. 

 Mr. Robertson Pratt showed capillitia of Myxomycetes and the 

 spirospores of a rare group of fungi. Mr. Edwin B. Matzke 

 showed cell shapes and their relation to soap films. Mr. Harold 

 C. Bold showed the fusion of the gametes of Botrydium. Mr. 

 Watkins showed paired chromosomes of Yucca. 



Professor William Bonisteel exhibited cinchona bark and 

 terrariums. 



The New York Botanical Garden put up some exhibits on 

 evolution and leaflessness in cacti; development of phyllocladia 

 from the combined leaves of Acacia; adaptations to an epiphytic 

 habitat; development of ferns from spores; some odd methods 

 of vegetative propagation; and some valuable plants for school 

 and class work such as Rhoeo discolor which was particularly 

 suitable for studies of stomatal movements; the Date Palm 

 which is readily grown from seed, etc. 



The Boyce Thompson Institute for Plant Research, under 

 the direction of Dr. William Crocker, showed injury due to ethyl- 

 ene gas on tomatoes and sunflowers, and demonstrated a method 

 for showing transmission of gas through plant tissues; the stimu- 

 lating effects of ethylene chloral-hydrate on dormant gladiolus 

 corms; the effects of the low temperature stratification on the 

 germination of a number of kinds of seeds of trees and shrubs; 

 the dependence of many kinds of plants on the proper length of 

 daylight for flowering and fruiting; and photographs of Dr. 

 P. W. Zimmerman's work on vegetative propagation, particu- 

 larly emphasizing the importance of making cuttings of the size 

 and degree of maturity which are best for each kind of shrub. 



Dr. R. P. Wodehouse of the Arlington Chemical Company 

 showed examples of his work on pollen grains and pollen grain 

 development. 



Dr. A. B. Stout of The New York Botanical Garden showed 

 some interesting types of plant variegation and particularly fea- 

 tured the work of one of his students, Professor Keur of Long 

 Island University, on the Transmissible Virus Mosaic of Abuti- 

 lons. He also showed microscopical slides of pollen germination, 

 the influence of the pistil on these and some of the peculiarities 

 of the pollen growth in incompatible crosses. 



