Vol. Xxi] ENTOMOLOGICAL \K\VS. 267 



outline, frequently slightly crescentic, and measure about .72 

 mm. long by .21 mm. broad (average of 20 specimens). The 

 egg itself is slightly smaller, .63 mm. by .18 mm. It is elongate, 

 white and delicate, slightly curved in at the middle portion. 



In the summer eggs are deposited in a large number of 

 plants, in the petiole or in the larger veins of the leaves. In 

 June, 1909, 1 cut through petioles of apple leaves and found the 

 eggs imbedded therein. They were placed immediately under 

 the surface of the petiole, lying longitudinally, with the curved 

 ends outward. 



The newly hatched leaf hopper is almost entirely pale, and 

 measures about .8 mm. long. After food is taken into the body 

 the abdomen becomes dull yellowish. Leaf hoppers in any 

 certain stage were found to vary considerable in measurement 

 from day to day. Averages from 10 specimens of each stage 

 were made and these results were obtained : Stage I, i.oo mm. ; 

 II, 1.26 mm.; Ill, 1.56 mm.; IV, 1.86 mm.; V, 2.26 mm. The 

 adults were 3.41 mm. long (average from 20 specimens). 



In Iowa there are four rather definite generations of this 

 species. The first generation comes on during May, and com- 

 prises only nymphs hatching from eggs in apple bark. During 

 June the second generation appears, this generation being com- 

 posed of the progeny of the first and also of the hibernating 

 adults. The generations appear about a month apart, the last 

 one coming out the latter part of August. Straggling nymphs 

 are found well into October. Winter eggs have been found in 

 apple bark as early as September 10. 



Typhlocyba rosae Linn. 



Egg pouches were found at Shenandoah on elm trees, in 

 wood two or three years old. They were not uncommon and 

 had the same appearance as those of Empoasca mail on apple 

 or of Empoasca obtitsa on poplar. A few days later young- 

 pale nymphs were found on these elm trees, as well as on soft 

 rnaple trees, on which no egg pouches were found. It seems 

 probable, however, that there were also eggs deposited in the 

 maple bark. No traces of any adults aside from th<>- "f /'///- 



