June, 1914-] Woodruff : Dragonflies of a Connecticut Brook. 157 



the brook being unsuited to open water species. It was eminently- 

 suitable, however, for certain of the Gomphinae, and of these Ophio- 

 gomphiis johannus was the largest and most conspicuous, with its 

 rich green thorax and broadly spatulate abdomen plainly apparent as 

 it hunted low after the manner of its kind. By no means abundant, 

 it was yet apt to be found wherever the brook's bed widened suffi- 

 ciently to disclose uncovered gravel along its edge. 



This species, when ready to abandon its nymphal existence for 

 that of the image, leaves the water at some sandy or gravelly margin 

 where, resting on the ground or on the side of a stone close to the 

 water's edge, it awaits the splitting of its dorsal covering, and slowly 

 drags itself from its prison house. The metamorphosis takes place 

 toward the end of May, and even on sunny days occurs several hours 

 after sunrise. 



As the nymph is as yet undescribed I present herewith a brief 

 description based upon the exuviae. ^ 



Next in size, but much rarer, was Gomphus hrevis, a species in- 

 cluded in the New Jersey list, but distinctly northern in its range. 

 Nothing distinctive concerning its habits was noted on this occasion, 

 the mere fact of its presence in the state alone entitling it to mention. 



And lastly the dainty little Lanthus albistylus, hardly larger than 

 the Argias, swift-flying, and resting preferably on stones not over an 

 inch or so above the surface. While but one female of this species 

 was taken, the males were found sparingly all along the course of the 

 brook under observation ; but always singly, each apparently excluding 

 his confreres from his own particular hunting ground. 



Except for Argia mocsta putrida, fairly common, and hunting 

 and resting for all the world like a Gomphus too, this part of the 

 brook was not attractive to many other Zygoptera, the only other 

 species noted being a very few Enallagma geminatum, exsulans and 

 ehrium, all exceedingly abundant further down its course, the omni- 

 present Ischnura verticalis, and one Chromagrion coiiditiim, the latter 

 the only one ever taken by me at Litchfield. 



Making a brief digression to the west of the brook, we come upon 



a small, cold, spring-fed pond. Its shores are for the most part 



steep and rocky, and all well wooded ; but an occasional narrow 



stretch of sand and stones, gay with rose pogonias and pitcher plants 



1 Published in this Journal ^'ol. XXII, p. 61. 



