E^SECTS : WINGS AND THEIR APPENDAGES. 



89 



scales proper are all marked witli loBgitudinal lines, 

 very minute and close, but they mostly bear a central 

 band, and sometimes a marginal one on each side, of 

 spots set in sinuous lines like the bands on a macker- 

 el's back ; these are probably composed of pigment- 

 granules. 



These from the pretty Six-spot Burnet Hawkmoth, 

 are nearly opaque, especially those from the red parts 

 of the wings, which have a rich ruddy glow by trans- 

 mitted light. They are narrow in shape, tapering 

 gradually forward from the foot-stalk, and terminate 

 mostly in two blunt points. Tlie ribs are coarse for the 

 size of the scales, and the depressed spaces are marked 

 with irregular pigment-grains. 



The hairs with which the bodies 

 of Moths are invested arc essentially 

 of' the same character as the scales 

 which clothe their wings. Here are 

 examples from the glowing sides of 

 the abdomen of that richly coloured 

 insect, the Cream-spot Tiger-mouth 

 {Arctia vilUca). You see they are 

 simple scales, drawn out to an inor- 

 dinate length and great tenuity ; each 

 has its quill-like foot-stalk, and we 

 may trace on some of them the ribs 

 and transverse dotting, while here we 

 see all intermediate stages between 

 the slenderest hair and the broadly 

 ovate, bluntly -pointed scales from the battledoob scale of po- 



LYOHMATUS ALEXIS. 



Wings. 



Tou are familiar of course with the brilliant little 

 Blue Buttei"fly {Polyommatus Alexis), which dances 



