OF THE PINE-APPLE. 



339 



ever, may be easily prevented by dusting snuff or 

 tobacco-dust upon them when in that tender state. 

 The Onisci breed in the tan, on which they seem 

 in a great measure to subsist. 



5. The Coccus Hesperidum e , commonly called 

 the Brown Turtle Insect. This has been already 

 described on account of its being generally found 

 upon the Pine-apple plant : however, as it in- 

 habits many plants, both in the hot-house and 

 green-house, I judge it proper to take notice of it 

 again. 



These insects may be destroyed, at a certain 

 age, by fumigation : therefore, in hot-houses where 



e The Coccus is of the Order Hemiptera. 

 Its Characters are : 

 The rostrum of the Coccus is situate in the breast. 

 The hinder part of the abdomen is bristly. 

 The Coccus has six feet. 



The males have two wings, which, when at rest, are in- 

 cumbent. 



The females are without wings. 



The female Cocci fix themselves and adhere, almost im- 

 movably, to the roots, branches, and leaves of plants, where 

 they are visited by the winged males, which are of a size con- 

 siderably smaller. Some of them having thus fixed themselves, 

 lose entirely the form and appearance of insects ; their bodies 

 swell, their skin stretches, and becomes smooth, the segments 

 of their abdomen disappear, and they so much resemble some 

 kinds of galls or excrescences found frequently on the leaves 

 and branches of plants, that in general they are mistaken for 

 such. 



In some species the males are but few in number, in propor- 

 tion to the females, and their duration is exceedingly short. 



z °Z 



