NOV., 'o6] ENTOMOLOGICAL NEWS. 351 



Plathemis subornata (Odonata). — Among some dragonflies recently 

 received from Ernest Oslar are specimens of the above species. Refer- 

 ences to this species are rare ; in fact in addition to Hagen's notes, I 

 know of only one other, a passing reference by Ris,* excepting, of 

 course, its occurrence in catalogues (Kirby and Banks). For this reason 



a brief note on characters and distribu- 

 tion as shown by Oslar's material may 

 not be out of place. In fully adult 

 males the wing coloration, by the in- 



UB DEPRESSA PLA LYDIA ' . , .7 < , I . rf. 



crease in density of color between the 

 two wing bands, becomes almost indis- 

 tinguishable from Plathemis lydia. The 

 most reliable character I have found for 

 separating the two species in such a 

 t subornata p subornata ' case is the form of the bifid ventral tu- 



bercle on the first abdominal segment, as shown in the accompanying 

 figures. As shown, subornata is somewhat variable, but can never be 

 mistaken for lydia. I cannot detect any structural character for separa- 

 ting the females of the two species. Other characters separating them 

 are : subornata, 9> abdominal segments 9 and 10 largely black ; 5-8 with 

 lateral spots continuing the direction of spots anterior to them, not 

 lowered to the lateral carina; antehumeral stripe or vestiges present; 

 wing apices not dark ; lydia, 9 , abdominal segments 9 and 10 largely 

 pale brown; 5-8 with lateral spots touching lateral carina, not in line 

 with spots anterior to them ; antehumeral stripe wanting ; wing apices 

 dark. 



One 9, Albuquerque, New Mexico, July, 2r, 1902, is like lydia in all 

 characters, excepting that the wings lack the apical dark area. This 

 specimen lacks any hint of the second or distal wing band present in sub- 

 ornata. In fact its wing markings rather suggest Libellula forensis. I 

 regard it, however, as certainly lydia. Another 9 of lydia (Albuquer- 

 que, New Mexico) has a trace of a subapical brown spot behind the 

 stigma, as in subornata. This gives each wing 4 spots. Oslar's collect- 

 ing contains specimens from the following localities : — subornata : Albu- 

 querque, New Mexico, July 17, 1902, and without date labels ; Gallinas 

 Canon, New Mexico, July 23, 1902; Rio Grande, New Mexico, July 12, 

 1902, and without date labels ; Pagosa Springs, Colorado, June 30, 1899 ; 

 Berkeley Lake, Colorado, June 15, 1898, and without date labels ; lydia : 

 Albuquerque, New Mexico, July 17, 21 and 27, 1902 ; Rio Grande, New 

 Mexico, July 12 and 27, 1902, and without date labels ; Arroyo, Pecos 

 River, New Mexico, July 12 and 17, 1902, and without date labels ; Berke- 

 ley Lake, Colorado, June 15 and 30, 1898, and July 23, 1901 ; Sloans 

 Lake, Denver, Colorado, June 1, 1898.— E. B. Williamson. 



* And Needham and Cockerell, Psyche, 1903, p. 135. After writing the above I notice 

 that Dr. Calvert has made use of the same characters of the bifid tubercle in treating of 

 Mihornata in Biol. Centr.-Amer. Neur. p. 205, Oct., 1905. 



