7 i6 INDEX. 



fcope, 14; his compound microfcope defcribed, 16; his 

 method of meafttring the magnifying power of the compound 

 microfcope, 58 ; his method of fixing ohje&s intended to be 

 drawn, 139, 



Hill, Sir John, his mode of preparing branches of trees, for ob- 



fervation, 158, 162. 

 Hemerobius perl a defcribed, 373. 



Hydra, many fpecies of defcribed, 398 ; their food, and method! 

 of feizing their prey, 409 ; generation of, 415, 



j ft $Mr - : *W . }d ; 



Jan fens and Son, microfcopes made by them, 2. 



Infects, a fcientific account of, 167 ; antennae of defcribed, 175 ; 

 legs ditto, 179 i wings ditto, 182; particular characters of;. 

 185 ; how claffed by Linnaeus, 187 ; their transformation, 189 

 the larva of, 193 ; pupa of,. 197 ; their refpiration, 240 ; 

 generation of, 248 .; eggs of, 265, 269 ; their multiplication, 

 271 ; food of, 272 ; habitation of, 278 ; wings of, 367 ; elytra, 

 of, 368 ; eyes of ditto, 375.. 



L 



Lieberkuhn, Dr. his microfcope defcribed, 7 ; his folar ditto,. 

 Leeuwenhoeck's microfcopes ditto^ 7. 



Lucernal microfcope,, invented by G. Adams, 22; it's peculiar 



advantages, 65 ; fully defcribed; 67. 

 Light rays ufed as a folar microfcope, 78 ; it's apparatus, 79 



experiment made with, 29; of the management of the, 131. 



Lenfes^ 



