68 MAINE AGRICULTURAL EXPERIMENT STATION. I916. 



The color is yellow and the dark markings become quite pronounced 

 toward the time for moulting and the cast skins of this instar show very 

 distinct transverse bands. Length 1.2 mm. 



3rd instar: In this instar there is a distinct black mark on the margin 

 between the vertex arid front at middle and next the eye and traces of 

 dusky markings on the frontal arcs and across the abdominal segments 

 two to seven. The vertex is distinctly shorter than in the preceding 

 instars and the beginning of the wing pads is distinctly indicated on 

 the mesothorax by expansions of the lateral border but on the meta- 

 thorax they are scarcely indicated. Length, 2 mm. 



4th instar: The color markings are as in the preceding instar. Head 

 shorter, the wing pads more distinctly developed, those of the meso- 

 thorax extending back half way on the meta-thorax and those of the 

 meta-thorax reaching the hind border of the first abdominal segment. 

 Length 2.5 mm. 



$th instar: The head is but slightly less produced than in the preced- 

 ing stage and about as in the adult and the black markings are clearly 

 marked. On the abdomen pairs of black transverse spots are distinctly 

 evident on segments four to eight. The spines of hind tibiae number 

 about eight. The wing pads of the mesothorax are much longer reach- 

 ing to base of fourth abdominal segment, those of the meta-thorax 

 also longer but reaching only as far as the mesothoracic pads on the base 

 of the abdomen. Length 3 mm. 



In all instars there is a nearly uniform number of the tibial and ter- 

 minal abdominal spiines though there seems to be a general increase in 

 number, those of the tibiae ranging from six or seven in the first instar 

 to eight or nine in the last. The beak extends usually to base of the 

 third coxae. The bristle on the third segment of the antennae persists 

 but becomes less and less evident as it does not increase in size in pro- 

 portion to the other parts. 



As nearly as can be determined by the season's observations 

 there seems to be one generation developing in grasslands 

 before July ist at which time the adults appear in new oat fields. 

 A later generation develops in the oats between July 15th and 

 August 15th and the adults and this generation appear to mi- 

 grate either to volunteer oats or other cereals or to grassland. 

 A generation develops doubtless between August 15th and Oc- 

 tober 1 st. The autumn generation possibly deposit eggs which 

 hibernate, although this point has not been determined with 

 certainty. The field cages showed few specimens of this species 

 and their exact hibernation is a question for this region. 



It will be seen from the habits indicated that the species 

 cannot be controlled upon quite the same basis as some of the 

 other leafhoppers and especially with reference to their at- 



