Microscopical Essays. 



225 



clearly) to fix the rank of this infecl: in animated life, and point 

 out thofe orders of being, and the moral ftate through which it 

 receives it's form and habits of life. 



The fnout is black and hard, the back part is quite folid, and 

 fomewhat of a globular form, whereas the front, f, is fharp and 

 hollow ; on the back part three membranaceous divifions may be 

 obferved, by means of which, and the mufcles contained in the 

 fnout, the infecl: can at pleafure expand or contract it. 



The tail is conftru&ed and planned with great fkill and wifdom. 

 The extreme verge, or border, is furrounded by thirty hairs, and 

 the fides adorned with others that are fmaller ; here and there the 

 large hairs branch out into fmaller ones, which may be reckoned 

 as fingle hairs. Thefe hairs are all rooted in the outer fkin, 

 which in this place is covered with rough grains, as may be 

 feen by cutting it off, and holding it up, when dry, againft the 

 light, upon a thin plate of glafs. By the fame mode you will 

 find, that at the extremities of the hairs there are alfo grains like 

 thofe of the fkin ; in the middle of the tail there is a fin all open- 

 ing ; within it are minute holes, by which the infecl: takes in 

 and lets out the air it breathes. The hairs are very feldom dif- 

 pofed in fo regular a manner as they are reprefented in Fig. 3; 

 Plate XL except when the infecl floats with the body in the 

 water, and the tail with it's hairs a little lower than the furface, 

 for they are then difplayed exactly as delineated in the 

 plate. The leaft motion downward of the tail produces a con- 

 cavity in the water, and it then afiumes the figure of a wine glafsv 

 wide at the top, narrow at the bottom. 



The 



