BEAUTY OF STRUCTURE 73 



It is a contrivance that commands our ad- 

 miration although we are acquainted with but 

 a few of its actions and uses. 



Its exquisite beauty, the minuteness of its 

 thousands of springs, and the finish of its 

 mechanism have led many a man to reflect on 

 his own impotence, and have suggested to his 

 mind something of the sublime skill that must 

 be behind all that we are pleased to call 

 1 Nature.' 



The specimen, photographed for the accom- 

 panying illustrations, in order to show its histo- 

 logical structure, has been opened out and its 

 lobes spread apart so as to present a thin section 

 for microscopic examination. 



Only a portion of the proboscis is shown in 

 either instance. The maxillary palpi and most 

 of the muscular parts are purposely omitted. 



A symmetrical system of canals pervades 

 each lobe. These are made up of spring-like 

 structures arranged side by side, which at first 

 remind one of the tracheal system of the water- 

 beetle Dytiscus ; but on closer examination they 

 are seen to be not spirally arranged, but forming 



