The Genus Perilestes 7 



On the position at rest and in flight, we made the following note on 

 remotus at Cristalina. In so far as we did not in the field recognize mag- 

 dalenae as distinct it is probable the note will apply equally well to both 

 species. ''Rest with abdomen hanging, wings half spread, and with the 

 last four abdominal segments often curled up over the back. Flight swift, 

 abdomen 'dragging'." And at the same locality on February 14, we 

 noted of both sexes: "Flies till at least 4:30 P. M., when the ravine is 

 dark and gloomy. Always rests with the abdomen hanging but the flight 

 is strong. JNIales frequently hover head on just as Heteragrion does. At 

 rest they are easily caught in the fingers." Of attenuatus, J. H. W. noted, 

 "First male seen (at Abuna) hanging with folded wings from tip of leaf 

 eight feet above the ground; the second was flying in the woods a few 

 inches above the ground." 



On pairing habits we have the following note on remotus, made at Cris- 

 talina: "Female hung from vine; male alighted on the apex of her abdo- 

 men and walked, up to her head which he held byi his feet while he 

 fastened his appendages. He then filled his seminal vesicle, kicking 

 the female vigorously about the head with his hind legs while doing 

 so. Copulation followed immediately, and then the seminal vesicle was 

 filled again, with more kicking." And at Villa Murtinho, J. H. W. 

 noted of solutus: "Saw a female resting on an almost horizontal twig. 

 A male came up from below and grasped her, she apparently aiding 

 by using front legs. They then flew to a perpendicular twig about 

 a foot away and the tip of the male's abdomen was brought for an 

 instant into contact with his genitalia. Female then brought the tip of 

 her abdomen to genitalia. After a second or two the sun was clouded and 

 I captured the pair by catching the male by the wings, in my fingers." 



Sources op jMaterial and Methods of Study 



We are indebted to Mr. Morton and Mr. Kahl for the privilege of study- 

 ing certain specimens as indicated under each species in the material 

 studied. The bulk of the material available to us, representing by far the 

 larger number of all known specimens, has resulted from two of our collect- 

 ing trips. Of first importance is the Brazilian collection made by J. H. Wil- 

 liamson and John W. Strohm, in 1922. The other trip which resulted 

 in considerable material in this genus was the University of Michigan- 

 Williamson Expedition to Colombia. We failed to find Perilestes on our 

 trips to British Guiana, Trinidad, Venezuela and Peru. This was espe- 

 cially surprising to us in Venezuela, but the suitable streams (as we under- 

 stand them) which we collected in Venezuela were on the north side of 

 the mountains. Evidently the Magdalena species, doubtless derived from 

 the Amazonian headquarters, have been able to work northward into 

 Central America, but have not spread eastward across the Maracaibo 

 region into the Venezuelan streams flowing into the Caribbean. 



In this paper, in the section Generic and Specific Characters, we have 

 explained the method followed in counting the wing cells, posterior to Cu,. 



