The Life of the Fly 



as a tiny grub a few millimetres long, it is 

 streaked with two different kinds of stains, 

 some white, opaque and of a creamy tint, 

 others translucent and of the palest amber. 

 The former come from adipose masses in 

 course of formation; the second from the 

 nourishing fluid or from the blood which laves 

 those masses. 



Including the head, I count thirteen seg- 

 ments. In the middle of the body these seg- 

 ments are well-marked, being separated by a 

 slight groove; but in the fore-part they are 

 diflicult to count. The head is small and is 

 soft, like the rest of the body, with no sign of 

 any mouth-parts even under the close scrutiny 

 of the lens. It is a white globule, the size of a 

 tiny pin's head and continued at the back by 

 a pad a little larger, from which it is separated 

 by a scarcely appreciable crease. The whole 

 is a sort of nipple swelling slightly on the 

 upper surface; and its double structure is so 

 difficult to perceive that at first we take it for 

 the animal's head alone, though it includes 

 both the head and the prothorax, or first seg- 

 ment of the thorax. 



The mesothorax, or middle segment of the 

 thorax, which is two or three times larger in 

 diameter, is flattened in front and separated 

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