40 NBW YORK STATE MUSEUM 



Miarj^in;!l noldios from I lie I wo olhcr- lesser lolws Cpl.8, fij;.8). The 

 iiiiddhi ](An' of the Iow<m' Ifiinellji is likovvise flat, but narrow, 

 linejir, and willi aiWeller (levelopnient of llie two othnr lobes at 

 ils b;ise. There is a sli<;ht decrejise in lenj^h on sej^rnents 2-7; 

 and on 2, and aj^ain on 7, the anterior of the three loljes of the 

 ni^tjier Jjinielia is seareely developed. Setae tliree, fragile, slender, 

 with minute apical wiiorls of wjjinules on the sej^ments. 



Color olivaeeouw brown ailxjve, with a variaible middle pale line, 

 fenestrate ujjon th<; doi-suui of the alidoinen with j^aler olivaeeous. 

 J>«dow, with a bi-o;id jiaU^ nu'dian ai-ea. 



Sever.il of my nym'[)lis from F;ill ereek liave colonial Vorticel- 

 lidae attached promiscuously ahout the dorsufni, or aj^gregated 

 about the bases of the setae. 



ri.8, ii^A, shows the venation and flj!;.2 of the same plate shows 

 the fonn of the a.ji-jiendaf^es of the male imaj^o in this species. 



Baetis pygmaea Ifaj^en 



This dainty little mayfly, which I described in bulletin 47 (pp. 

 421-42:{, pi. 15, fig.l3 and 14), I bred also from nymphs obtained 

 in Fall creek with tliose of the y>receding species, and I took a 

 few specimens of the imagos in trap lanterns hung about the 

 creek during July 1001. 



Callibaetis skokiana \e<'dham 

 I wish to record here concerning this species that I have made 

 a careful examination of mi(ios<opic mounts of the stomach con- 

 tents of ten well grown nymjihs taken from the (lym pond on the 

 campus of I^ke Forest College in Illinois, and liave found them 

 containing no recognizable animal remains wliatever, but only 

 remains of pl;inl tissues, chiefly the disintegrating fragments of 

 the dead leaves of the higher i)lants, such as litter from the 

 Xiond bottom, with a scanty sprinkling of algae— Cy a n o p h y 

 ceae ;ind st:ilked diatoms. 



Blasturus cupidus Say 

 I have found his species common in Six Mile creek at Itluica, 

 where I bred it in 181)7. I liave apparently identical nymphs in 

 my colhM-tion from Klkhart, Indiana, and H;ileigli, North Caro- 

 lina. The imagos of this genus appear in late spring. As be- 

 fore remarked, Berry has described the nymph in the American 



