to this are the three thoracic so^'inents, whicli carry on the 

 upper tergite the wings, and on the lower sternite the three 

 pairs of legs, as seen in the lar\ a. Then there are the eight 

 abdominal segments, each of which usually bears a pair of 

 spiracles, concluding with the two genital segments. The 

 head has a number of appendages. At either side is a 

 large eye, the size apparently being regulated by the speed 

 at which the insect travels, the swiftest having the largest 

 eyes. The eye is built on a strong chitinous ring, and is 

 covered with the facets so well known to microscopists, and 

 present the appearance of honeycomb ; sometimes the eyes 

 are naked, sometimes clothed with hairs which project 

 between the sutures of the hexagons. The eyes of insects 

 have been the subject of much investigation, but I do not 

 remember seeing a record of the chitinous ring. In some 

 species the ey^ are beautifully coloured, in shades of grey 

 and black on part of the surface ; the eye is largely loose, 

 and can be turned round to expose a surface that is not 

 ornamented. The markings do not appear to be constant, 

 but vary in individuals as much as do the markings on 

 birds' eggs. Between the eyes are the antennae, which are 

 so diverse in form that they alone would form a life-long 

 study. They are undoubtedly an organ of sense, i3iit 

 whether analogous to one of our five known senses is still 

 a mystery. There is one significant point that is worth 

 noting, that wherever variation exists in the sexes the 

 antennae of the male are always more elaborate than those 

 of the female. We now come to the mouth organs, which 

 consist of a long tongue composed of two halves of a 

 cylinder, which together form a complete sucking tube, at 

 the tip of which are usually a number of papillae ; the 

 tongue curves up vertically, and is protected at either side 

 by a palpus. The palpi are often pointed, and generally 

 possess an organ that, so far, I ha\ e not seen noticed. In 

 the lepidoptera we are so constantly on the look-out for 

 scent organs and scent glands that it is quite customary to 

 put down any ornamentation confined to one sex as a scent 

 organ ; as this organ in the palpi is not confined to either 



