110 MICROSCOPIC OBJECTS. 



and along with it the cross strise. In such cases the longi- 

 tudinal Hues only can be visible. The damaged specimens 

 are easily kno^vn by their paleness. 



(3.) " Alucita pentadactylus and hexadactylus (the Ten- 

 plumed and Twenty-plumed Moths.) — The structure of 

 the wings, or more properly plumes, of these insects, is 

 so pecuhar that few persons acquainted with Entomology 

 are strangers to it. 



"The Twenty-plumed Moth is more delicate in its 

 form than the other. The feathers or scales employed as 

 proof- objects must be taken from the body of the insect, 

 and not from the plumes or wings. Their breadth is 

 generally greater than their length, and their form is 

 never symmetrical. They are transparent and about the 

 one-hundred-and-eightieth of an inch long. The scale 

 is often partially covered by a dehcate, uneven, mem- 

 branous film, which obliterates the lines on those parts. 

 The longitudinal lines are not difficult to resolve ; but 

 their proximity is such that they require a considerable 

 power and careful illumination to separate them distinctly. 

 They are elegant microscopic objects, but rather scarce. 



(4.) ** The Lyccena. — The feathers of aU the species of 

 these small butterflies are charming subjects for the 

 microscope, the studded blue {Lycmna Argus) in parti- 

 . cular. As proof-objects the lined specimens have nothing 

 remarkable ; those from the inferior side of the wing are 

 of a bright yeUow colour, and the spaces between the 

 lines very transparent. The spotted scales found along 

 with these wiU be noticed hereafter. 



