1899] PEAR AND CHERRY SAWFLY. 103 



the tail is so small that sometimes it has been passed over, and the 

 larva classed as twmty-iooted. 



After the final moult to the yellow-coloured non-slimy state, the 

 caterpillars leave the food-plant, and bury themselves a little below 

 the surface of the ground, where they spin a somewhat cylindrical 

 obtuse-ended cocoon (see fig. 3, magnified, p. 101) ; this is only about 

 one-quarter of an inch in length, and, from the adherence of the 

 surrounding particles of earth to the silky web cocoon spun round 

 itself by the larva, is very difficult to distinguish from the ground in 

 which it lies. Under common circumstances, the cocoons, as far as I 

 am aware, are made singly in the earth, and at a distance of about 

 from half an inch to two or three inches beneath the surface, but, as 

 mentioned by Mr. Cameron, when the larvfe are very numerous, the 

 cocoons are spun close to each other ; and in the course of last 

 summer, in a case in which the conditions of ground did not fully 

 allow of the usual arrangements, some such interesting observations 

 of some of the cocoons being sheltered amongst large Pear roots, and 

 some being formed into clusters composed of several scores, were made 

 by Mr. Robert Newstead, F.E.S., Curator of the Grosvenor Museum, 

 Chester, and kindly placed in my hands, that I have pleasure in 

 inserting his notes with three of his series of illustrative photographs 

 (see pp. 105, 100). 



Within the cocoons the caterpillars change to the chrysalis state, 

 from which, although some of the Sawflies may develop in the same 

 season, the main brood (in this country) does not make its appearance 

 until the following year ; the exact rate of development, and the 

 extent to which the infestation may be double-brooded here, appears 

 to be variable, or at least not matter of certain record. 



The Sawflies (see figure, with lines giving natural length, at p. 101) 

 are rather less than a quarter of an inch in length, black, shiny, and 

 rather downy, or pilose, with the horns (antennaa) rather longer than 

 the fore body (thorax) ; legs black or fuscous, or with the shanks of 

 the anterior and middle legs respectively testaceous and fuscous; from 

 differences of description, the colouring of the legs appears to be 

 variable. The four wings transparent and iridescent, with a smoky 

 band across the middle. 



The above are the stages of the infestation most commonly ob- 

 served, those connected with the egg deposit, which starts the attack, 

 being on such a minute scale as to require a magnifying glass to 

 distinguish the details. 



The places of egg locality, as I have occasionally seen them myself,* . 

 are to be found in the upper side of the leaf as little spots roundish in 



* See ' Observations of Injurious Insects,' by E. A. Ormerod, during 1893, 

 p. 81. 



