MAY FLIES AND MIDGES OP NEW YORK 47 



this Eaton describes as beiug entire. Otherwise, there is close 

 agreement. The length is 7 mm. in male, 8 mm. in female; setae; 

 10 mm. in male, 6-7 mm. in female. The segments of the male 

 fore tarsus in order of diminishing length are 2, 3, 4, 5, 1, the 

 first segment being one fifth as long as the second. The legs 

 are wholly pale. The setae of the male are strongly ringed with 

 black except at the extreme tip in the male, wholly pale in the 

 female. The head and thorax and basal segments of antennae 

 are brown. The abdomen in the male is rufous, paler on the 

 middle segments, and sufl'used with brownish apically above; in 

 the female abdomen there are broadly triangular transverse basal 

 bauds of paler on the middle segments. The posterior prolonga- 

 tion of the sternum of the 9th segment in the female abdomen is 

 deeply divided by a wide U-shaped notch. The abdominal appen- 

 dages of the male are shown in pi. 10, flg.9. 



Ephemerella excrucians Walsh 



In Bulletin 47 I published a description of the nymph of this 

 species (pp.425-426), bred at Saranac Inn. On June 30, 1901, 

 Mr. J. O. Martin gave me a live nymph which he had just col- 

 lected from the shore of Cayuga lake, and I reared this also. 

 Since that time I have received a large number of specimens from 

 dift'erent places in Indiana, notably from Elkhart, sent me by 

 the late Mr R, J. Weith. From some of the latter, selected to 

 show the great variety in depth of color pattern, I have had a 

 new photographic figure made, which I present herewith (pl.9, 

 fig.l). It will serve immediately for comparison with the very 

 different form of nymph found in the species above described. 

 On pi. 10, fig.8 are represented the abdominal appendages of the 

 male imago. 



? Caenis allecta, sp. nov. 



This is the commonest species in Fall creek at Ithaca. It 

 swarmed into trap lanterns hung about the creek during July. 

 Its nymph lives in the pools and side channels of that turbulent 

 stream, w^here the water flows gently among small rock frag- 

 ments over a bottom thinly strewn with silt. Imagos of our 

 smallest species, Oaenis hilaris Say, come to the trap 

 lanterns with this one, but in smaller numbers; its nymph I have 

 not found. 



