140 DIRECT INJURIES CAUSED BY INSECTS. 



somewhat at each extremity ; consisting of twenty arti- 

 culations without the head : Head reddish brown, heart- 

 shaped, much smaller than the following joint; armed 

 with two unguiform mandibles; with a biarticulate pal- 

 pus attached exteriorly to the base of each. These man- 

 dibles appear to be moved by a narrow black central 

 tendon under the dorsal skin terminating a little beyond 

 the base of the first segment ; besides this, there are four 

 others, two on each side of it, the outer ones diverging, 

 much slenderer, and very short. The last or anal joint 

 of the body very minute ; exerting two short, filiform 

 horns, or rather respiratory organs. I could discover, in 

 this animal, no respiratory plates, such as are found in 

 the larvae of Muscidce, fyc. nor were the tracheae visible. 

 When given to me, it was alive and extremely active, 

 writhing itself into various contortions with great agility. 

 It moved, like other dipterous larvae, by means of its 

 mandibles. Upon wetting my fingers more than once, 

 to take it up when it had fallen from a table upon which 

 it was placed, the saline taste with which it was imbued 

 was so powerful that it was some time before it was dissi- 

 pated from my mouth. I shall only mention one more 

 instance, because it is a singular one. The larva of 

 Helophilus pendulus, a fly peculiarly formed by nature 

 for inhabiting fluids, has been found in the stomach of a 

 woman a . 



You will smile when I tell you that I have met with the 

 prescription of a famous urine-doctor, in which he recom- 

 mends to his credulous patient to take a certain number 

 of sow bugs per diem, by this name distinguishing, as I 



a Philos. Mag. ix. 366. 



