Occasional Papers of the Museum of Zoology 39 



Colombia, February 17, 191 7, collected by J. II. and E. B. 

 Williamson, collection of E. B. W. 



In the itinerary of our trip to Colombia" I have described 

 (page 17) the small tributary of the Ouebrada Sabaleticus 

 where we found Mesagrion. We collected along the Quebra- 

 da Sabaleticus only a short distance aljove this small tribu- 

 tary. On the afternoon of February 17 I heard black howlers 

 up the quebrada as 1 came out of the small tributary, so fol- 

 lowed up stream- as much to see the monkeys as to collect 

 dragonflies. After finding the monkeys and seeing one make 

 ,a splendid leap, I was returning to the tributary about 3 130 

 p.m. when I saw a Heteragrion resting on the twig tip of a 

 small dead bush which had lodged on a bit of sand and debris 

 in mid-stream. It occurred to me that the insect was general- 

 ly duller than the common inityatitni. ^loreover we were 

 capturing every uiifratitiii that came readily to hand to make 

 sure that we were not overlooking some similar species. So 

 the specimen resting on the dead twig was netted, and its 

 specific distinctness was recognized before it was dropped 

 into the cyanide bottle. A brief search in the neighborhood 

 resulted in the capture of specimens of iiiifratiiin onl)-. Two 

 days later J. W. made a special trip up the Sabaleticus to look 

 for the females of Alesagrion and for this new Heteragrion 

 but he failed to find either. The brilliant metallic areas on the 

 vertex have suggested the specific name. 



25. Heteragrion mitratum, new species 

 Figures 3, 4, 50, 51, 56, 63, 69, 95. 162, 163 

 Abdomen, male ^6 to 40 mm. ; female 29 to 30.5 : hind wing, 

 male 21.5 to 24; female 23 to 24.5. 



]\Iale. — Rear of head light yellow; genae, face and anterior 



^* A Collecting Trip to Colombia, South America, Mis. Publ. No. 3, Museum 

 of Zoology, Univ. of Mich. 



