178 



lower surface. Many sun leaves of Ruhus allegheniensis de- 

 veloped sunburn spots in the center of each leaflet. Ripe fruits 

 of Vaccinium pennsylvanicum partially dried on the plant. 

 Leaves of Diervilla lonicera growing in the full sunshine developed 

 sunburn to a marked extent. In fact, only a few plants escaped 

 and so thoroughly was the color developed that patches of 

 Diervilla on hillsides became visible at a long distance. 



All of these effects may be referred to the unusually high 

 transpiration, caused by high temperatures, wind, and low 

 humidity, and furthered by the low water content of the sandy 

 soil, on which no rain had fallen in ten days. 



To obtain some idea of the reduction in leaf temperature 

 caused by transpiration, the crude experiment of wrapping a 

 leaf around the bulb of a thermometer was used. A single 

 thickness of the leaf, with the lower surface exposed, was held 

 around the bulb with a pair of forceps, and the temperature 

 noted after 30 seconds exposure. Leaves of Acer ruhriim pro- 

 duced no depression of temperature at all, and also showed 

 greater evidence of immediate injury than any other plants on 

 which the experiment was tried. Populus tremidoides caused a 

 depression of one to two degrees, while Populus grandidentata, 

 known to transpire at a more rapid rate, produced two to four 

 degrees depression. Gaultheria procumhens, surrounded by an 

 air temperature as high as 112° when the experiment was tried, 

 produced an average depression of over four degrees. 



THE PECK TESTIMONIAL EXHIBIT OF MUSHROOM 



MODELS 



By Homer D. House 



It is peculiarly fitting at this time to describe rather briefly 

 the exhibit of mushroom models, recently installed in the State 

 Museum at Albany, N. Y., as a memorial to the life and services 

 of the late Charles Horton Peck, state botanist of New York 

 from 1867 to 19,15, a period of forty-eight years, all except the 

 last two years having been spent in active service. 



