318 Annals Entomological Society of America [Vol. IX, 



body and toward the dorsal surface; when ready to leap a sud- 

 den straightening of the setae in a posterior direction lifts the 

 larva into the air. In this way the larva can leap five or six 

 miUimeters. This method of jumping is quite different from 

 that of the cheese-maggot, Piophila casei, and some of the Iton- 

 ididae which leap by first bringing the head and tail ends 

 together and then suddenly straightening the body. A third 

 method of locomotion occurs when the larvae are on a moist 

 surface, when they crawl by extending and contracting the 

 body segments. 



On September lOth, the larvae were separated into two lots 

 and were liberated in large petri dishes which contained bark. 

 A few spiders of the genus Epeira and spider's eggs were also 

 placed in the dishes with the larvae. In both dishes most of 

 the larvae died after three days and in five days no living larvae 

 were found, though the spiders seemed to be normal and fed 

 upon flies for several days. 



On September 27th, or 17 days after confinement, one of the 

 smallest spiders was found in a dying condition. The abdomen 

 of this specimen was removed and carefully dissected. Three 

 spiny larvae were found in the body near the dorsal surface. 

 The larvae were alive and active and showed no change other 

 than a distension of the body segments. 



Some time later the cephalothorax and legs of this same 

 spider were cleared in carbol-xyol and mounted in balsam. 

 This method rendered the thorax almost transparent and 

 enabled one to locate the parasites in their exact position. In 

 all, twenty-seven larvae were found in the cephalothorax and 

 legs. These were found in the following parts : One in the first 

 segment of the right palp, one in each trochanter of the anterior 

 pair of legs, two in the trochanter of the second right leg, one 

 in the femur of the third right leg, one in the femur of the 

 fourth left leg, one in the patella of the fourth left leg, and the 

 remaining nineteen were in the cephalothorax above the ental 

 openings of the coxae or near them (Fig. 10). 



On November 29, 1915, a second spider died. The death of 

 this specimen was doubtless due to injury received while moving 

 the specimen from Ohio to Illinois, for the thorax was dented 

 and one leg partly crushed; however, it lived for seventy-nine 

 days after it had been put with the young Cyrtid larvae. This 



