2l6 



Microscopical Essays. 



The egg of the rhinoceros * beetle is of an oblong round figure, 

 of a white colour ; the (hell thin, tender, and flexible ; the teeth 

 of the worm that is within the fhell come to perfection before the 

 other parts ; fo that as foon as it is hatched, it is capable of de- 

 vouring, and nourifhing itfelf with the wood among which it is 

 placed. The larva, or worm, is curioufly folded in the egg, the 

 tail refting between the teeth, which are difpofed on each fide 

 the belly « the worm, in proper time, breaks the fhell, in the 

 fame manner as a chicken, and crawls from thence to the next 

 fuitable fubftance. 



The worm, when it is hatched, is very white, has fix legs, a 

 wrinkled naked body, but the other parts all covered with hair: 

 the head is then alfo bigger than the whole body, a circumftance 

 which may be obferved in larger animals, and which is founded 

 on wife reafons.f If the egg is obferved from time to time while 

 the infect is within it, the beating of the heart may be perceived. 



The eggs of the earth-worm, the fnail, and the beetle, will 

 afford many fubje&s for the micro fcope, and will be found to 

 deferve a very attentive examination. Swammerdam was ac- 

 cu Homed to hatch them in a dim, covered with white paper, 

 which he always kept in a moift flate. To preferve thefe and 

 fuch like eggs, they mud be pierced with a fine needle ; the con- 

 tained liquors muft be preffed out, after which they mould be 

 blown up by means of a fmall glafs tube, and then filled with a 

 little rofm diffolved in oil of fpike. 



The 



* Scaraba^us Actceon, Lin. Syft. Naf. p. 541-3. 

 + Swammerdam's Book of Nature, pt. 1, p. 33. 



