146 



PRACTICAL MICROSCOPY. 



Stephanocerus Eichhornii is one of this class ; it is shown in 



Fig. 129. The author has before him at the present 



moment some leaflets of Myriophyllum spicatum, the 



common water -weed, completely 

 covered with Melicerta ringens, Flos- 

 cularia cornuta, Philodina megalo- 

 trocha, Limnias ceratophylli, Eu- 

 chlanis dilata, and Codosiga botrytis. 

 Most of these organisms may 

 be obtained from Mr. Bolton's 

 studio. 



Books which may be consulted (see 

 Animalcules). 



INSECTS afford an inexhaustible 

 series of treasures to the micro- 

 scopist; but in order to examine 

 these perfectly, a knowledge of dis- 

 section must be gained. The head, 

 eyes, legs, wings, proboscis, spiracles, 

 and tracheae, all make instructive 

 objects. Many are the kinds of 

 insects that can be pressed into the 

 microscopist's service, the Siphonop- 

 tera, or fleas; the Parasitica, or 

 lice ; the Diptera, or flies ; the 

 Hymenoptera, bees and wasps ; 

 Lepidoptera, butterflies and moths ; 

 Orthoptera, grasshoppers and cric- 

 kets ; the Coleoptera, or beetles, are 



all too well known to require instructions when, how, and 



where to collect. 



Fig. 130 shows the male Dytiscus marginalis, or great 



water beetle, a very interesting insect to the microscopist, 



while Fig. 131 is a picture of the female. 



FIG. 129. 



