107 



parasites beiug found in the roots of the parsnip, together with the 

 pupa cases of the moth. I have never examined the roots of the pUmt 

 to see if the Iarv?e did go down into them, but I presume they do so 

 when very abundant and can not iind sufficient accommodation in tlie 

 stalk itself, which is often very full of the silken cocoons of the pupte. 

 Many of the larvai had eaten through the nodes, and even the inter- 

 Jiodes of the stalk were perforated. The habits of entering the stalk at 

 the node seemed to be preferred, hoAvever, after the leaves and sheaths 

 had been devoured and under the frass collected at that point. 



The stalks of the parsnip in this field were so completely strii^ped of 

 every umbel and leaf that they presented nothing more than a mass 

 of dry sticks standing among the grass, and in this case materially 

 lessening the seed crop, and therefore the plants for the coming year. 

 Sometimes as many as five of the pupae would be alongside of each 

 other, but each in its own silken cell. 



The larv.ne taken by me in 1887 were found in the first week of July, 

 the most of them at that time having entered the stem to pupate. In 

 1888 it was the last week in June, and then aU were in active operation 

 under cover of their webs. 



No doubt birds do feed upon these larvae, and Bethune says the Hairy 

 Woodpecker {Picus villosus) visited the parsnip stalks in his garden 

 daily and pecked away at the larvae and pupae within. Although birds 

 abounded in the meadows and adjacent woodland, yet after several 

 years observation I have never seen a bird obtaining its food from this 

 source, although nothing could be easier to obtain, or more delicious 

 when obtained, than the larvae of this insect. I have examined hun- 

 dreds of webs, and while I have found many empty of larvae, I have 

 attributed their absence to be charged more against the Potter Wasp 

 than to the work of birds, who either do not know a good thing when 

 they see it or fail to see it altogether. 



I discovered that one of the worst enemies the Web-worm had was 

 the Potter Wasp [Eumenes fraterna), a veritable canine in propensities 

 for hunting and capturing the caterpillar. 



One of these wasps would alight on the umbel in which a web was 

 situated and would begin to peer into it first at one end, then at the 

 other, all the time getting more and more excited. On discovering 

 the worm within it would commence to run its abdomen into the end 

 of the web, with its head directed towards the opposite end, trying in 

 this way to eject the occupant, and every now and then darting at the 

 orifice as the worm would approach it. In this way it would work for 

 a long time, first at one end and then at the other, no doubt each time 

 thrusting out its sting. In this way it continued, packing the silken cell 

 at each end until it became too short to longer cover the larva and keep 

 out of reach of sting and jaws and it was forced to show itself, when 

 the mandibles of the wasp sank deep into it and it was dragged forth 

 from its burrow. Sometimes this was done with great difficultv but 

 6757— No. 2 4 ^' 



