of the SLUG WORM. 



the fting, or inftrument with which the female makes the 

 incifion for the reception of her eggs. This refembles a 

 faw,and from this circumftance they are called by Englifo 

 writers Saw-flies. One of the anterior and pofterior wings 

 is (hewn at fig. 9. The male refembles the female in 

 colour ; but is confiderably lefs and has no (ting. A part 

 oF the abdomen of the female, containing the fting, is 

 fhewn atj£g\ 10 ; and the correfponding part of the male 



'dtjig. il. 



In the thirteenth edition of the Linnean Syftem, by 

 Profeffor Gmeiin, there are 142 fpecies of this genus, of 

 which the Tenthredo Cerafi or Saw-fly of the Cherry-tree, 

 has the greateft affinity to the Slug-fly • and is defcribed 

 as bein<* "black, with the legs and triangular part on the 

 " back, between the infer tion of the wings, yellow. The 

 * ; larva /limy and black, inhabits the leaves of the Cherry 

 * tree, which it rolls up"* 



The Slug-fly has no yellow about it, neither does trie 

 larva roll up the leaves : it may, notwithstanding, be a 

 variety' of the Tenthredo Cerafi, as it agrees in fize and 

 in the fiimy covering. 



An eminent French author, on the fubject of infeBs, 

 has a figure of the fly and of the larva ; but defcribes only 

 the latter, which he calls the Falfe Caterpillar of the 

 Pear-tree. In his defcription he fays, " Another kind of 

 « falfe caterpillar, which differs very much from the com- 

 « mon kind in form and which it is difficult to chara&er- 

 6i ize is found on various fruit-trees, as the Plumb, the 

 " Cherry, but efpecially on the Pear-tree. Fruit-trees 

 " however are not the only ones on which they are found ; 

 " for I have alfo feen them upon Oaks. In both they 

 « live on the upper furface of the leaves, and there con- 

 « fume the parenchyma; their fkin is always mucous, 

 « which would make them to be taken for fnails, if one 

 " did not perceive their feet. Their colour is a brown- 

 * green. They are rarely ftretched out like the Cater- 

 €; pillar, and can at pleaiure fwell a certain part of their 

 6i body : they frequently fwell the fore part for a third 



46 of 



* Syftema Naturae, pa. .2659, no. 20. 



