Description of the Coccus Laricis. 171 



produced by a very minute species of Coccus, the form and 

 habits of which I will briefly state. In size it does not ex- 

 ceed that of a pin's head ; its form is ovate narrowing towards 

 the abdomen ; body convex, and surrounded by deep annu- 

 lar wrinkles ; the full grown female insect is of a slaty purple 

 colour : the eggs of a pale orange ; its proboscis is situated 

 very low in the breast, and appears to be the instrument 

 through which the cotton-like web, in which it envelopes 

 itself, proceeds. The female, when pregnant, swells to such 

 a bulk, that the legs and antennae can scarcely be perceived, 

 even with the assistance of a good microscope : having spun 

 out a quantity of cotton-like threads, and discharged several 

 globular drops of saccharine matter, she deposits therein from 

 twelve to twenty oblong eggs, and then dies : the external 

 husk of her body alone remaining, as a shelter for the eggs 

 and young ones. The male insect, I have not yet observed, 

 but it is no doubt a small winged fly, similar to that of other 

 species of this genus. 



My Larch Firs alone, were at first infested by this insect, 

 but from some cause or other, which I am unable to solve, it 

 has of late years deserted, in some measure, the Larch, and 

 attached itself to the Weymouth Pine and Silver Fir. Hav- 

 ing once exhibited this disposition to change, is it not possible 

 that it may ultimately invade our gardens, and unless its pro- 

 gress be arrested, become as formidable an enemy to plants 

 on the outside of our hot-houses, as the Coccus adonidum 

 is to those within ? 



In any case, this is a subject worthy of consideration, and 

 although its destruction upon a large scale might be difficult 



vol. in. A A 



