282 



Microscopical Essays. 



in, or in order to perceive more regularly at the bottom what 

 happens at the mouth, at which it forms a kind of door, made of 

 different layers of earth, conne&ed together by threads, and 

 covered with a ftrong web of a clofe texture ; the threads are 

 prolonged on one fide, and fixed to the ground, fo as to form a 

 ftrong joint ; the door is hung in fuch a manner, as always to fall 

 by it's own gravity. One of thefe cafes, or nefts, is in her 

 Majefty's cabinet at Kew. 



Infefts are found no where fo numerous as in trees and plants, 

 where they find abundant food. They dwell i. in the roots ; 

 2. in the wood; 3. in the leaves, and in the galls which grow 

 upon the leaves and branches ; 4. in the flowers ; 5. in the fruits 

 and grains. It would be too tedious to enumerate th$ various 

 fpecies of thefe inhabitants ; many particular obfervations have 

 been already noticed ; it has alfo been mentioned, that fome in- 

 habit the mo ft fcetid fubftances they can find, while others 

 dwell with and live on the larger animals ; fo that it only remains 

 juft to mention fome of thofe in whom induftry and art is more 

 ftrongly marked to our eyes than in others. 



Among the folitary bees there are fo many curious circum- 

 fiances to be defcribed, that a fingle volume would not fuffice to 

 contain the particulars ; we (hall here only relate fuch as concern 

 their habitations. One of thefe forms its neft under ground* 

 which is compofed of feveral cells artfully let into each other, but 

 not covered with a common inclofure ; each cell confifts of two 

 or three membranes, inexpreffibly fine, and placed over each 

 other. The cavity, in which the neft is placed, is fmeared over 

 with a layer of matter, like that of which the cells are formed, 



