114 MICROSCOPIC OBJECTS. 



in size they become more transparent. They are of different 

 forms, but possess a general character easily recognised 

 by the want of any sharp angles. Under a microscope 

 not having sufficient penetration, the tissue appears 

 devoid of structure or markings ; but when placed under 

 a superior one, and the illumination properly made, they 

 show a series of lines or cords on their surface, and pre- 

 sent a much greater variety in their arrangement than the 

 scales of any other species of insect. Some have the 

 lines straight, others are waved and curved, while on 

 some of the small ones nothmg satisfactory has yet 

 ])een developed." Their most usual appearance, however, 

 is, that of spines, arranged in various forms upon the 

 surface of the scale. Some observers consider that the 

 scale is covered with short hairs ; but the investigations 

 of Mr. Pritchard leave no doubt of their being Unes. 



"As a general rule, it wiU be found that the smaller the 

 scales the more difficult the test. I must not omit to 

 notice that the cords on these. scales are loosely attached 

 to the tissue, and are often rubbed off in mounting. Of 

 com'se it wiU be fruitless to examine such specimens." 



"Before leavingthe subject of the lined objects, I should 

 notice, that all objects of similar structure are more or 

 less tests, as the lines on the scales of some beetles, espe- 

 cially those from the Diamond Beetle (^CwrcwZ/o imperialisj. 

 The scales from the body of this Beetle, either as trans- 

 pai'ent or opaque objects, are by far the most brilliant, in 

 point of colour, of any of the hned class. In viewing 



