THE M UD-DA UBERS. 1 95 



thirty minutes the spider was dead. We repeated this experi- 

 ment with a lai-ge Thomisus, and with Dolomedes tenehrosus 

 and in both cases the stinging resulted in death at the end of 

 twenty hours. All of these spiders and many others were killed 

 by the general diffusion of the poison through the system and 

 not by any wounding of a ganglion. When we allowed a 

 considerable amount of venom to be injected death followed al- 

 most immediately but if a smaller amount w^as used the spider 

 lived a day or more. 



One experiment was tried upon a large caterpillar, the sting 

 of our large hornet, Yespa fiiaculata, being forced out and 

 pushed into the last segment, and some of the poison squeezed 

 into the wound. The effect of the venom was immediately 

 visible in the posterior third of the body. The anterior two- 

 thirds moved normally, dragging the end of the body along. 

 Perhaps this worked the poison forward for after a little all the 

 anterior parts became affected. An hour later the caterpillar 

 seemed shghtly better, but on the next day it was so much af- 

 fected that it could not turn over when placed on its back, mov- 

 ing only when stimulated. On the third day it was alive but 

 very sluggish, moving slowly when touched, and on the fourth 

 day it died. This was on the fourth of July. On the seventh 

 it was still soft and in good condition, but by the eleventh it 

 was quite dry. 



A large number of spiders that were killed in our experi- 

 ments were kept that we might note the time at which decom- 

 position began. We found that on the average they kept fresh 

 for ten or twelve days after death. We had only one which 

 began to decompose as early as the ninth day, and even in this 

 case the spider Avas in what a wasp larva would have considered 

 an edible state three or four days longer. All of our experi- 

 ments were in complete agreement with the condition of things 

 found in the nests, where many of the spiders were alive when 

 first stored but died from day to day, and whether dead or alive, 

 plump or dry, w^ere eaten eagerly and with apparent relish. 



The following table shows for eleven nests, of which we pre- 



