INSECTS. 133 



autumn, is also a species of Trombidium T. autum* 

 ndle. 



Preparation. The organs of the mouth, &c., of the 

 Spiders are easily prepared for examination, by care- 

 fully pulling them off with forceps or the mounted 

 needles, then drying them under pressure between 

 two glass slips, macerating in turpentine, and mount- 

 ing in balsam. Those of the Acarina should be dis- 

 sected out with the needles, after the body has been 

 crushed in a drop of water on a slide, and the internal 

 substance has been gently washed away with a hair 

 pencil. They may then be dried on a slide, with a 

 cover laid on, and turpentine applied to the edge of 

 the cover, balsam being added when most of this has 

 evaporated. The various parts may also be mounted 

 in chloride of calcium or glycerine. 



INSECTS. The members of the class of Insects are 

 extremely interesting to the microscopic observer, 

 not only on account of the beautiful structures which 

 they present, but also from these being comparatively 

 large, usually coloured, and easily distinguished under 

 the lower powers. Hence they form admirable ob- 

 jects for study to those who are but little accustomed 

 to the use of the microscope. 



MYBJAP'ODA (yitu/oto?, myriad, TTOI)?, foot. This 

 Order contains those insects which are popularly 

 known as the hundred-legs and millepedes ; by many 

 zoologists they have been arranged in a distinct 

 class. 



The most common member of this Order is Litho- 

 bius forcipdtus (PL X. fig. 4), which is found under 

 stones, in cellars, and among garden-rubbish. It is 

 of a yellowish-brown colour, with long, many-jointed, 

 gradually tapering or setaceous (seta, a bristle) anten- 

 nae (figs. 4 0, 5 fl), and two large and powerful mandi- 

 bles (fig. 5 b) resembling those of the spiders. It 

 has also a broad, notched, and toothed lower lip, or 

 labium (fig. 5 d), above which are two toothed jaws, 



