916 



ZOOLOGY INSECTS. 



states the absence of gills in living specimens of D. intricata and D. alpina. 

 Formerly, the genus Pteronarcys was the only known exception for its gill 

 bearino- imagos among the class of insects; now, besides the above 

 described Dictyopteryx, there are two other gill bearing Perlid genera 

 mentioned by Dr. Gerstaecker Damphipnoa litchenalis from Chili, a genus 

 closely related to Pteronarcys ; and Nemura cinerea and N. nitida, with its 

 male, N. lateralis, both from Europe. 



The papers by Dr. Gerstaecker are published in the Festschrift zum 

 hundertjahrigen Bestehen der Gesellschaft naturforschender Freunde, Berlin, 

 1873, 4to, p. 60, with figures; and Sitzungsbericht derselben Gesellschaft, 

 October 21, 1873, p. 99. 



Taken at Roaring Fork, Colo., by Dr. J. T. Rothrock. 



ISOPTERYX. 



ISOPTEEYX GYDIPPE, Hagen. 



Some specimens, much damaged, presumably of this species, were taken 

 in Southern New Mexico in September, 1874, by Dr. 0. Loew. 



FAM. ODONATA. 



OPHIOGOMPHUS. 

 OPHIOGOMPHDS SEVERUS, Hagen. 

 OpMogomphus severus, HAGEN, U. S. Geol. Surv. Terr., 1873, 591. 



Greenish-yellow; head and mouth parts greenish-yellow; labium and 

 labrum paler ; antennae black ; part between the eyes black, forming a 

 transverse black band above the base of the front, excised in the middle ; 

 vertex greenish- yellow, flat, the front margin deeply notched, the sides of 

 the vertex cariniform, curved in an exact semicircle around the lateral 

 ocelli; occiput greenish-yellow, with a small, black band along the superior 

 border, beginning near the occiput. Thorax greenish-yellow, an ill denned 

 brownish spot on the dorsum each side near the wings ; the crest of the 

 sinus not exceeding the bifurcation, black, and an incomplete blackish band 

 on the humeral suture beginning at the wings. 



(Three males and two females from Colorado, in alcohol ; a single male 

 from Yellowstone, preserved dry, shows the following pattern): Dorsum 



