REPORT OF THE ENTOMOLOGIST AND BOTANIST. 25$ 



trees. The second brood is more troublesome to us than the first, because at that season 

 fruit-growers are so busy that it is almost impossible to find time to spray with Paris 

 green." — L. Woolverton. 



" St. Catharines, Lincoln Co., Ont. — The Pear-tree Slug has done more damage than 

 most pests in this district, familiar as it is and easy to fight as it is. I think I am well 

 within the mark in saying that it has been far more destructive than in any season for the 

 past decade. The second brood worked very freely on the plum as well as on the quince, 

 cherry and pear, and thousands of young trees — particularly cherry — had their leaves 

 skeletonized." — Martin Burrell. 



The Plum Web-avorm {Lyda rujipes, Marlatt). — When travelling through the 

 Mennonite countrj' in Southern Manitoba in the first week of July last I noticed a great 

 deal of damage done to plum trees by the gregarious false-caterpillars of a saw-fly which 

 webbed together the leaves of SJiall branches and soon stripped them of all green cellular 

 portions in a very similar manner to the larvse of the Cherry-tree Tortrix (Cacoecia cera- 

 sivorana, Fitch). Upon examining the webs I found them to be filled with 

 enormous numbers of a false caterpillar of a species of saw-fly belonging to 

 the genus Lyda, which was quite unknown to me. The larvae were nearly 

 \ of au inch in length, grayish above, yellowish or pinkish below ; head 

 yellow, thoracic shield and feet as well as the tip of anal segment, black ; pro-legs 

 wanting. They have two seven-jointed antenna-like apj^endages, protruding from the- 

 front of the head, and also two others three-jointed, from each side of the last segment. 

 I was unable to rear the perfect insects, but T find a description of what is evidently the 

 same species by Pi*of. T. A. Williams in Bulletin 38, April, 1896, of the South Dakota 

 Experiment Station, in which the insect is described and figures are given of the perfect 

 insect, the cluster of eggs and a bunch of sand cherry infested by the larvte. It is de- 

 scribed as one of the most destructive insects attacking plums and cherries. It feeds 

 upon all the common forms both wild and cultivated. It is found most often on the 

 common wild plum (^Prunus Americana, Marsh) and the sand cherry (Prunus j^umila, 

 L.). Prof. Williams describes the mature insect as much flattened, with body, head, 

 antennae and feet shining black, legs reddish. iJe gives as the date of appearance of 

 the flies the second week of June. The larvge which I found in Manitoba were fuU- 

 growti in the first week of July, and at that time most of the plum trees in the gardens, 

 of the Mennonites over an area of many miles were almost entirely defoliated. 



The eggs are deposited in close masses along the under side of the mid-rib of the 

 leaf, the long axis of the eggs lying parallel with the mid-rib. The younger leaves are 

 invariably ^^elected, and the eggs laid before the leaf has expanded. Immediately on 

 hatching, the young larvae begin to spin a web and feed through or crawl over to the 

 upper surface of the leaf. As they continue to grow, they tra vel to other leaves and 

 envelop all in a tough web not unlike that of the tent caterpillar. A large colony will 

 spread over the whole side of a tree before the insects become full-grown. When ready 

 to pupate, the larvae go to the ground and gradually envelop themselves in cocoons, 

 turn to pupae and emerge again [the next year] in the late spring or early summer as 

 mature insects." — (South Dakota Experimental Station, Bulletin 4S). 



As a remedy, plum trees should be sprayed with Paris green or dusted with white 

 hellebore as soon as the webs appear. 



It is just possible that this insect may be the Lyda fasciata of Norton, described 

 and figured by Prof. A. S. Packard on page 524 of his Forest Insects under " Cherry 

 Insects." But, until specimens are secured of the Manitoba insect, it will be impossible 

 to identify the species with certainty. From the manner of occurrence of the colonies 

 seen in the Mennonite villages, the idea of an imported species is suggested, such as Lyda 

 pyri, Schrank, mentioned in Miss Ormerod's last report, as having caused a similar 

 injury in English orchards. Synonyms of the latter are also L. clypeata, Klug ; L. 

 fasciata, Curtis and West wood, and Pamphilius Jlaviventris, Cameron. 



The San Jos6 Scale (Aspidiotus perniciosus, Comstock). — An important discovery 

 has been made by Mr. R. M. Palmer of undoubted specimens of the San Jose scale in Van- 

 couver Island. Prom the appearance of infested wood forwarded, the pest must have 



