46 The Microscope. 



the two layers. I can easily lift them off with a knife, 

 and mount them for the microscope, while the skin 

 makes another very pretty object for ifc, not unlike 

 the spotted coat of a leopard. Four of the scales, and 

 the divided portions of the skin, are represented in 

 fig. 8; and fig. 9 is the smallest of these scales magni- 

 fied fifty diameters. The kind of network pattern is 

 of the same fineness on the larger scales. 



The account which Dr. Carpenter gives of this 

 apparent network is that the scale consists of " a 

 layer of isolated spheroidal transparent bodies, im- 

 bedded in a plate of like transparence;" and these, 

 he adds, " appear not to be cells (as they might 

 readily be supposed to be), but to be concretions of 

 carbonate of lime." These pretty little scales are 

 white, and, viewed as opaque objects, they look like 

 black lace ; viewed transparently they are like black 

 lace, or like white lace held up to the light. The 

 apparent holes are the " spheroidal transparent bodies " 

 described by Dr. Carpenter, and his remark on the 

 transparency of the layer which encloses them is 

 verified when the scales are mounted in balsam, as 

 they then become nearly invisible in all ordinary 

 modes of illumination. 



They appear, however, in much splendour in the 

 ft polarizing apparatus " of the microscope, to which 

 I have already alluded (p. 6) as one of the luxuries 

 which can be dispensed with by a purchaser who is 

 limited as to the price of his instrument. It can, 

 however, be added to most cheap microscopes of 

 good construction, and is, as a matter of course, an 



