EXPLANATION OF THE PLATES. 



It is to be understood, that all the figures given in the following plates 

 are magnified 670 times, unless when the contrary is stated. 



PLATE I. 



THE BLOOD OF MAN. 



Fig. 1. The hunian red blood corpuscle, showing its natural 

 form and appearance when brought fully into focus, 

 in which case the centre always appears light. 

 Scattered over the field will be seen one or two 

 white corpuscles. 



2. The same, with the centre dark, in consequence of 



the object not being brought fully into focus. 



3. The same in water, in which the red globules lose 



their flattened and discoidal form, becoming cir- 

 cular, and presenting a smaller surface to view ; the 

 white corpuscles at the same time, and under the 

 influence of the same agent, are seen to have 

 increased considerably in size. 



4. The same, united into rolls, as of miniature money in 



appearance. 



5. The same, showing the peculiar granulated and vesi- 



culated appearance which they so frequently pre- 

 sent under such different circumstances. 



6. The white corpuscles of the blood, in water, in which 



they enlarge considerably in dimensions, often 

 appear nucleated, and after long immersion burst. 



