44 



SCIENCE 



[N. S. Vol. XLV. No. 1150 



DISCUSSION AND CORRESPONDENCE 



A CASE OF SYNCHRONIC BEHAVIOR IN 

 PHALANGID^ffi 



A RECENT article in this journal by Wallace 

 Craig on " Synchronism in the Rhythmic 

 Activities of Animals " recalls to mind an ob- 

 servation that I made near Austin, Texas, in 

 1909. At the time of the observation I made 

 some field notes from which the following de- 

 scription is taken. 



While engaged in hunting various species 

 of rock lizards I located a vast colony of 

 " harvestmen," which I identified as belonging 

 to the genus Liohunum, resting during the 

 day on the under side of an overhanging shelf 

 of rock on a precipitous hillside. In a some- 

 what circular area of nearly five feet in diam- 

 eter the harvestmen were packed closely to- 

 gether in almost unbelievable numbers. I esti- 

 mated that there were between one and two 

 thousand in the colony. Wlien I first saw 

 them they were all hanging from the ceiling, 

 as it were, perfectly motionless, but when I 

 came within about six feet of them they began 

 a curious rhythmic dance. Without changing 

 their foot-holds they raised their bodies up and 

 down at the rate of about three times a sec- 

 ond, and, curiously enough, the movement of 

 the entire lot was in the most perfect unison. 

 This performance was kept up for over a 

 minute and then stopped gradually as though 

 from exhaustion. I then poked a few of the 

 nearest individuals with a stick and these 

 immediately resumed the rhythmic up-and- 

 down movement, which spread quickly over 

 the whole group, but died down in less than 

 half a minute. When I once more stirred up a 

 few individuals they gave a few rhythmic re- 

 sponses, which stirred the whole colony again, 

 but only slightly. After this a number of indi- 

 viduals began to crawl about and it was no 

 longer possible to stimulate the rhythmic 

 behavior. 



When the colony was first seen it was noted 

 that the long legs of neighboring individuals 

 were closely interlocked and this mechanism 

 was sufficient to accoimt for the transmission 

 of stimuli from one part of the colony to an- 

 other. It should be noted especially that the 

 rhythm was not perfectly synchronous at the 



beginning, but became so after a few seconds. 



Possibly synchronic flashing in fire-flies may 

 be explained as the result of a somewhat sim- 

 ilar transmission of stimuli. One flash stimu- 

 lates others, which at first might lag slightly; 

 but soon a synchronism is built up in a limited 

 region, such as one bush or one tree. Such a 

 synchronism might be transmitted to a whole 

 field. 



It would be interesting to know whether any 

 other naturalist has observed the type of be- 

 havior herewith described for the Phalangidae. 



H. H. ISTewman 



University or Chicago 



THE SUPPOSED SYNCHRONAL FLASHING OF 

 FIREFLIES 



I WAS very much interested in reading the 

 article by H. A. Allard, entitled " The Syn- 

 chronal Plashing of Fireflies," which appeared 

 in Science, ISTovember 17, 1916. Some twenty 

 years ago I saw, or thought I saw, a synchronal 

 or simultaneous flashing of fireflies (Lampy- 

 ridas). I could hardly believe my eyes, for 

 such a thing to occur among insects is cer- 

 tainly contrary to all natural laws. However, 

 I soon solved the enigma. The apparent phe- 

 nomenon was caused by the twitching or sud- 

 den lowering and raising of my eyelids. The 

 insects had nothing whatsoever to do with it. 

 Many times in the past twenty years I have 

 proved that my solution was correct. 



Philip Laurent 

 trimmed magazines and efficiency 



EXPERTS 



To THE Editor of Science: I have been 

 reading your article on page 13 of Science 

 for January 5 entitled " Science and the Cost 

 of Paper " and am very sorry that the price 

 of paper has increased to such an extent that 

 you have to make a material change in Sci- 

 ence. I understand your position and am not 

 objecting the slightest to what you are doing; 

 but I do want to make a protest against this 

 popular efficiency humbug, because it seems 

 to me that people are running the efficiency 

 matter into the ground. It's all nonsense for 

 any efficiency expert to say that the opening 



