314 



SCIENCE 



[N. S. Vol. XLVI. No. 1187 



kers 80 that it would be possible to determine the 

 species and thus know if it is abnormal habit. 



The nest in question consisted of a globular 

 portion which was abruptly contracted below 

 into a long, slender, vertical neck of practically 

 uniform diameter. This slender neck served 

 as the only means of entrance into the struc- 

 ture. 



The writer wishes to state that he once 

 found one of these unique nests at Oxford, 

 Mass., many years ago. This nest was kept 

 as a curiosity in the writer's collections for 

 many years and did not fail to excite the 

 wonder and admiration of those who saw it. 

 In size and shape this nest was similar to the 

 one found by Newhall at Shelburne, Mass. 

 Newhall states that he found his specimen 

 under the eaves of a building. As well as the 

 writer can remember, the nest which he found 

 at Oxford, Mass., was suspended from a small 

 branch of a tree not far from the ground. The 

 maker of the nest was never seen. Although 

 the writer has always kept a sharp eye open 

 since for other specimens of this kind, none 

 has ever been seen. It would be of consider- 

 able interest to know whether the two unique 

 nests in question really represent abnormal 

 deviations of habit for some well-known spe- 

 cies, or the normal habit of nest-construction 

 for a very rare and little known, or even un- 

 known, species. H. A. Allard 



Washinoton, D. C. 



synchronism in the flashing of 

 fireflies 



The articles on the flashing of fireflies which 

 have appeared from time to time in Science 

 have aroused my desire to experiment upon 

 the subject. The presence of two individuals 

 of the firefly, Photuris pennsylvanica DeG., 

 in my tent at the University of Michigan 

 Biological Station at Douglas Lake, Mich., on 

 the evening of July 17, 1917, gave me my first 

 opportunity. With the tent dark, I watched 

 the two fireflies for about ten minutes. For a 

 while they flashed alternately, but it soon be- 

 came apparent that one was flashing a trifle 

 more frequently than the other. Consequently, 

 once in every two and one half to three min- 

 utes flashing was simultaneous. Then for 



about twenty minutes I experimented with a 

 three-celled vest jwcket flashlight with the fol- 

 lowing results. I could easily get in rhythm 

 with the firefly, but I could not make the fire- 

 fly change its rhythm and keep with me. Some- 

 times the fireflies would stop while I was flash- 

 ing the light and again they would continue 

 to flash after I stopped flashing. At no time 

 could I control their flashings. The flashlight 

 and the two fireflies flashed simultaneously 

 when I synchronized with one of the fireflies 

 until its time interval brought it into coin- 

 cidence with the other. 



On the evenings of July 19 and 25, 1917, 

 I had opportunity to carry the experimenta- 

 tion fiurther — on each occasion with a single 

 firefly. The same kind of results were ob- 

 tained from these experiments. However, I 

 discovered that when I brought the flashlight 

 within 25 centimeters of the firefly it ceased 

 flashing and did not recommence until after 

 I had ceased flashing or until I had moved 

 the flashlight back a meter or more. 



On many evenings at the College of Agri- 

 culture of the University of the Philippines, 

 at Los Banos, I have watched splendid fire- 

 flies, of which there are large nmnbers in the 

 immediate vicinity. I frequently noticed that 

 small trees and shrubs would be more aglow 

 at certain times than at others, but I never 

 happened to observe a time when a small tree 

 or shrub was all alight one instant and dark 

 the next. In my experience there were al- 

 ways some fireflies flashing in the " dark " 

 periods. The times of greatest light occurred 

 when the greatest number of varying flashes 

 coincided. 



From these observations and experiments 

 it seems to me that complete synchronism in 

 the flashing of a group of fireflies is simply 

 a very rare accident, occurring when the 

 flashes of the individuals chance to come at 

 the same time. Frank C. Gates 



Carthage College, 

 Carthage, III. 



UREDINIA OF CRONARTIUM RIBICOLA ON 

 RISES STEMS 



During the past season uredinia of Cronar- 

 tium ribicola Fischer have been discovered for 



