GAKDEN^ FLEA-HOPPER IX ALFALFA. 19 



The female assumes the usual feeding position in which the body 

 is parallel with the surface of the leaf. Apparently after a desirable 

 place is located with the proboscis a puncture is made ; the curved or 

 swordlike ovipositor is then advanced to the puncture made by the pro- 

 boscis immediately after the removal of the proboscis; the ovipositor 

 penetrates the puncture to its full length, and an egg is deposited 

 in the cavity. ^Vfter the ovipositor is withdrawn a large drop of clear 

 fluid exudes from it, covering the exposed truncate end of the egg. 



The process of oviposition requires about 15 to 20 seconds, only 

 one egg being placed in each hole. 



EFFECT OF TEMPERATURE ON OVIPOSITION. 



It was found that oviposition ceased when the temperature fell 

 below 70° F., and there were no records of oviposition at tempera- 

 tures above 90° F. In a number of cages (fig. 16) each containing two 

 male and one female flea-hoppers were placed in a well-ventilated 

 basement room of the laboratory, the temperature of which ranged 

 between 75° and 90° F., most of the eggs were deposited in the 

 daytime when a temperature of about 80° F. was reached, which 

 usually occurred in the early morning. 



EGG STAGE AND PROCESS OF HATCHING. 



Several days before hatching the egg changes from its original 

 pearly white to a pale clay-yellow color, this change being evidence 

 of its fertility. The color of the egg resembles that of the nymph at 

 emergence. The shape and position of the nymph, including the 

 segments of the abdomen, the thorax, the head, the appendages, and 

 the carmine-colored eyes, are distinguishable under a lens. In the 

 egg the nymph is found with its head at the truncate end a short 

 time before hatching, the covering of this end being broken at the 

 edge or through the middle, and opening, in most cases, like a trap- 

 door. The head appears through the opening followed by the thorax 

 and abdomen. The body moves backward and forward in an effort 

 to disengage the appendages from the chorion. The appendages are 

 all laid snugly against the ventral side of the body. The proboscis 

 is the first appendage to be released, followed by the prothoracic and 

 mesothoracic legs. These are then utilized to free the antenna} and 

 metathoracic legs. The entire process requires about one hour. 



The egg is slightly swollen before hatching. Following the emer- 

 gence of the nymph the eggshell coUapses and is semitransparent 

 with red pentagonal to polygonal markings. The body and legs of 

 the freshly emerged nymph are i)ale clay-yellow color, the antennae 

 straw color, and the eyes carmine. The egg period was found to 

 range from a minimum of 6 days to a maximum of 16 days in the 

 experiments carried out, with an average incubation period of 11 

 days. 



