NEW RECORDS OF WISCONSIN DRAGONFLIES 



(0 DON ATA.) II. 



By Richard A. Muttkowski. 



The following records are largely from specimens taken by 

 the Museum Expedition of 1910 along the Mississippi river, from 

 N. Hudson, St. Croix Co. to Fountain City, Buffalo Co., Wis. 



The chief est element of interest in the expedition was the 

 influx of western forms, less noticeable in Odonata than in other 

 orders, whose distribution is more dependent on extraneous fac- 

 tors. This was one of the most noticeable features of the 

 collections. 



Several extraneous records are included in this paper, chiefly 

 for the purpose of figuring the characters of the species, hitherto 

 not figured. It is well to note that I am obliged to Mr. E. B. Wil- 

 liamson for the loan of specimens to illustrate Ccenagrion reso- 

 lution and Ischnura prognatha. The remaining figured species 

 are mentioned in the text. 



AGRIONIN^. 

 Agrion aequabile (Say). 



In the material collected along the St. Croix river 1 , a large 

 variation in markings is perceptible. The largest of the series 

 agree perfectly with Hagen's description of the race hudsonica 2 , 

 while the smallest are identical with specimens taken at Milwau- 

 kee and at points farther south. 



On comparing a series from Milwaukee with a similar series 

 from the St. Croix region, it is possible to note several differences, 

 which, however, are probably of local origin. 



The differences cited by Hagen, namely "more bulky in head, 

 thorax and abdomen," hold good for the St. Croix specimens. 

 Another difference, "wings more strongly tinged," also applies 

 to the St. Croix material. It likewise applies to specimens from 

 Washington and Chippewa counties. 



1) See the Bulletin of this Society, Vol. 8, p. 54, 1910. 



2) Psyche, Vol. 5, p. 247, 1889. 



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