May, 1920] Studies in Food of Spiders 225 



some attraction for this spider and one can often find them in a 

 clearing by pulhng the bark off an old stump. 



To one who can see the humorous side in the action of 

 animals, I know of nothing of more interest than watching one 

 of these spiders. When one of them encounters a large insect 

 or another spider, he holds his head erect often turning it aside 

 like a dog intently listening and lifts up one of his front legs as 

 if to say, "I have the right of way." 



Phidippus is a bold spider and will attack insects much 

 larger than itself. I have found one sitting on the side of a 

 stump eating a male cockroach {Ischnoptera pennsylvanica) tw<y 

 or three times the size of the spider; another one in blackberry 

 bush eating a Vespa germanica. I have noted them in a rail 

 pile eating grasshoppers several times the size of the spider. 

 One which was kept in captivity ate a bald-faced hornet,. 

 Vespa maculata. As I did not see him capture the hornet I am 

 unable to say as to whether the hornet died and the spider 

 seized it after it had died or whether the spider killed it. I 

 think the latter to be the case as I have never seen this spider eat 

 an insect that has died a natural death. 



It is interesting to watch one of them stalk such an insect 

 as Lygus pratensis. One sunny afternoon I saw one of these 

 spiders after a Lygus pratensis in a patch of tall weeds. The 

 insect evidently was aware of the presence of the spider but 

 seemed to misjudge the danger. It flew from one branch of the 

 weed to the other with Phidippus audax constantly on its traiL 

 The spider reminded one of a squirrel up in a big tree jumping 

 from one branch to another, now descending a short distance, 

 running out on a limb, now jumping to another tree, and run- 

 ning up the trunk to a more favorable situation for another 

 jump. He kept up the hunt for sometime, each time he was 

 about ready for the fatal jump, the insect flew to another 

 branch of the weed but his stealth and persistence won. Slip- 

 ping up a branch from the rear he jumped onto the insect. I 

 took the insect from him immediately but it was already dead. 



How this spider as well as Agelena ncevia and the Lycosids 

 can kill an insect so quickly has long puzzled me. In J. Henry 

 Fabre's book entitled, "The Life of the Spider," is an explana- 

 tion which seems to solve the problem. Mr. Fabre says the 

 spider sinks the chelicerae into the insect's ganglion, which is 

 the only place that a thrust from the chelicerae would cause 



