HAGEx.] ZOOLOGY PSEUDO-NEUEOPTERA AND NEUKOPTERA. 581 



er ; Chicago, by Osten Sacken and Woodwell ; Maine, in Harris's col- 

 lection. 



This is the E. natata of my synopsis. The species imitates E. vulgata, 

 of Europe, but the wing§ are more grayish than brownish. It differs 

 from E. decora by the larger size, the darker marked wings, the less 

 annulated setae, the relative length of the joints of the appendages. At 

 least, there can be no doubt about the difference of my E. natata and E. 

 decora, brought together even with E. guttulata, a,s belonging to the 

 same species, by Mr. Eaton. 



It may be interesting to publish here a letter to the late Prof. L. Agas- 

 siz by Mr. George E. Woodwell, from the Tribune office, Chicago, 111., July 

 23, 186 (!) (number not filled). The letter contained several dry speci- 

 mens, imago and subimago, of E. natata : 



I send you a number of specimens of a fly ■which annually visits our lake-cities, and 

 which has the present summer appeared in larger swarms than ever known before. 

 During the recent hot nights they have poured in from the lake in myriads, rendering 

 it necessary in lighted buiklings to close the windows and doors in order to escape their 

 visitation. For several nights past, they have thus swarmed upon us ; and vhe morning 

 would witness about the posts of the street-lamps large heaps, in some instances three 

 inches deep, and covering an area of two or three yards square. 



Couriously enough, the imitating species from Europe, E. vuJgata, 

 swarms in a similar manner ; and Scopoli tells us that the farmers in 

 Krain are not contented unless they are able every year to bring a num- 

 ber of cart-loads as manure upon their fields. 



HEPTAGENIA. 



H. hrunnea, sp. nov. 



Male imago. — Brown, the thorax and the body beneath paler ; head 

 blackish ; prothorax deeply notched behind, with an elongated blackish 

 spot on each side, and a similar one on the mesothorax ; metathorax 

 bright-yellow between the wings. Abdomen brown, the segments with a 

 darker ring on the tip ; setse long, grayish-brown, darker at the base, 

 the articulations scarcely darker ; appendages long, cylindrical, darker 

 brown, four jointed ; first joint very small ; second somewhat longer 

 than the apicals together, which are of equal length ; piece between 

 the appendages notched ; penis long, bifid, divergent. Femur paler on 

 the tip ; the other legs pale-brown ; femora with a darker external line ; 

 tarsi dark. Wings hyaline ; veins brown ; some transversal veins on the 

 costal margin pale. 



Female imago. — Similar to the male. Abdomen pale, on the upper 

 portion of each side a series of triangular black spots and a longitudinal 

 between them ; beneath, on each side a series of black lines ; setae pale, 

 articulations black ; egg- valve broad-elliptical ; legs similar, the four 

 posterior with the tarsi pale ; femora darker, pale at the base and tip ; 

 wings similar, the transversal veins in the costal space pale, very fine, not 

 reaching the costa. 



Length, 5,10 millimeters; 9, 12 millimeters 5 alar expansion, <J, 

 30 millimeters ; $ , 34 millimeters. 



Habitat. — One pair from Nevada, Truckee, in Sierra Nevada range, 

 June 10 (J. E. Crotch). 



H. pudica. 



Syn. — Ephemera pudica, Hagen, Synop., i]9, 5. 



Female subimago (dry, just casting the skin). — Grayish-brown ; head 

 large, triangular, flattened, luteous ; eyes distant, black ; posterior ocelli 

 large, the anterior small j antennas short, stout, brownish, paler at the 



