Objects for the Microscope. 93 



its brown wings, most excellent test objects, and giving 

 different markings. When dry, or in balsam, or when 

 viewed by oblique or direct light, we see that the rounded 

 end is toothed, and bears a brush-shaped appendage. 



SCALES OF PONTIA BRASSICA. 



The common Cabbage Butterfly, whose history is too 

 well known to need remark ; the earliest and latest of our 

 summer friends and garden enemies. There are several 

 shapes in the scales of its wing, a very long and slender one, 

 and some more of the battledore shape, and heart-shaped, 

 with beautiful striae. Observe also a portion of the mem- 

 brane, where the scales or feathers are rubbed oif. The 

 apertures into which they are fixed are little cups or tubes, 

 the orifices of which are set backward ; and around each 

 are radiating folds of the upper membrane, giving them a 

 star-like appearance. 



SCALES OF THE SILKWORM MOTH. 



The Silkworm Moth (Bombyx mori) has a variety of 

 scales, toothed, and broad or narrow, and Leuwenhoeck 

 reckoned no less than 400,000 of these delicate scales on 

 the wings of one moth. 



SCALES OF CLOTHES MOTH. 



From the under side of that troublesome little Tinea we 

 obtain a beautiful test object of very fine striae. Also from 

 the Podura. 



SCALES OF PODURA. 



The Podura is a small gray wingless insect with six legs, 

 and a long forked tail, bent inwards, and by means of 

 which it leaps and springs about in the sawdust of our 

 cellars, and under stones, and in moss in damp places. 



SCALES OF LEPISMA SACCHARINA. 



A first cousin of Podura, haunting our sugar stores, and 

 originally a native of America. It does not leap so well as 

 Podura, if at all ; for its body does not terminate in a forked 

 tail, but in several long thread-like styles, and it runs 

 swiftly along, the little silvery gray body closely covered 



