70 ENTOMOLOGICAL NEWS [Mar., '22 



of the male lydia, while in the female it appears only in rare 

 examples. 15 Subornata should probably be associated with the 

 group of southwestern primitives, foliata, nodisticta and com- 

 pos it a. 



Group 7. Nodisticta Hagen. PI. IV, fig. 12. Montana and Wash- 

 ington 10 to the highlands of southern Mexico. A semidesert species 

 taken by the writer on slow fresh streams at Oroville and Auburn, 

 California. 



Forensis Hagen. PI. IV, fig. 13. Montana and British Columbia 

 to Arizona and California. An alkali pond species, but may occur in 

 fresh water also. 



Pulchella Drury. PI. IV, fig. 14. Maine to Washington south to 

 Florida and California. A strictly fresh pond species. 



The writer does not know the locality of the Washington 

 record for nodisticta, but it must be near sea-level. The Mon- 

 tana record is probably from a warm, spring-fed stream, while 

 all other United States records are from elevations of 500-3000 

 ft. Southward it is found at constantly increasing elevations 

 until its southernmost authentic record is at 8000 ft. in More- 

 los, Mex. This would indicate that the Venezuelan and Co- 

 lombian records in the earlier literature are questionable, for it 

 is not probable that the Isthmus of Panama has been elevated 

 enough to enable this species to pass into South America. 



In this group specialization is towards a wing heavily spotted 

 with black, alternating with areas of white pruinescence. It 

 starts with the lightly marked wing of nodisticta, throws a spe- 

 cies, forcnsis, more heavily marked, to the desert and reaches 

 its apex in pulcJiclla with three full bands in each wing. These 

 species may not form a series as they have had to be arranged 

 on the plate, but may be a group of mutations from some more 

 primitive stock. The large size and the great development of 

 wing color in pulchclla indicate that it is the most specialized 

 of the three. The distribution of nodisticta indicates that its 

 naiad cannot endure heavy freezes, while the distribution of 

 pulcJiclla shows it to be almost as hardy as 4-niactilata and 

 julia. 



15 Kennedy. Odonata of Kansas, Bull. Kans. Univ., vol. 18, pi. VII, 

 1917. 



16 Muttkowski. Cat. Odonata N. Amer., p. 138. 1910. 



(To be continued ) 



