ern Florida. Although the winter range is still unknown in fullest 

 detail, Lincoln (1944b) has shown that some of these birds spend the 

 winter season in northeastern Peru. 



Although the idea that hibernation is a regular feature of the life 

 cycle of birds is no longer accepted for any species, recognition must be 

 accorded the observations of Edmund C. Jaeger of Riverside College, 

 Riverside, Calif. (1949). Earlier (1948), he had given a brief account 

 of the behavior of a poorwill found during the winter of 1946-47 in 

 the Chukawalla Mountains of the Colorado Desert, Calif., and which 

 was in a state of profound torpidity. 



What was presumably the same individual was found in the same 

 rock niche in a comatose condition on November 26, 1947. Beginning 

 on December 30, 1947, rectal temperatures were taken every 2 weeks, 

 the last on February 14, 1948. The temperature dropped from 67.6° 

 on the first date to 64.4° on January 18 and February i, recovering to 

 65.8° on the late date of record. The weight decreased from 45.61 

 grams on January 4 to 44.56 grams on February 14. An attempt to 

 detect heart beat by the use of a medical stethoscope was negative. No 

 movement of the chest walls could be detected and no moisture could be 

 collected on a cold mirror placed in front of the nostrils. Strong 

 light aimed directly into the pupil resulted in no response, not even an 

 attempt to close the eyelid. No waste matter was passed during the 

 entire period of observation and all evidence indicated that the bird 

 was in an exceedingly low state of metabolism. 



This bird was banded on January 5, 1948, with a Service band and 

 was back in the same rock niche on November 24, 1948, certainly the 

 second and probably the third season of return to this exact point. It 

 was there on December 5, 1948, but 2 weeks later it had disappeared, 

 probably the victim of some predator or an inquisitive human. Pro- 

 fessor Jaeger reports that the Hopi Indians call the poorwill 

 "Holchko," the sleeping one. 



Aristotle also was the originator of the theory of transmutation, 

 basing it upon the fact that frequently one species will arrive from the 

 north just as another species departs for more southerly latitudes. 

 From this he reasoned that although it was commonly believed that 

 such birds were of two different species, there really was only one, and 

 that this one assumed the different plumages to correspond with the 

 summer and winter seasons. 



889511— 5C 



