NATURAL HISTORY OF SELBORNE. 
413 
friend, tlie late Professor Quekett, told me that when staying 
in tlie country, he once offered a penny each to the village 
children for harvest bugs for the microscope; in a few minutes 
he was obliged to retract his offer, tliey were so plentiful. The 
harvest bug is smaller than the mite ; it can just be seen in the 
cracks of the skin of the hand. It sticks to the skin by means 
of two short arms situated above the upper legs; it feeds by 
means of a tubular snout. My secretary, Mr. Sear I e, informs 
me that vinegar allays the itching, and it is supposed kills them. 
I wish I liad space to say something about the parasites which 
infest human beings, especially about that curious parasite the 
guinea-worm, or Dracimculus. Whales are troubled with para- 
sites somewhat like bugs, with formidable hooked claws to 
hold on by; there are some fine specimens in my museum. 
The Horse Gadfly, p. 125. — When Assistant-Snrgeon to the 
2nd Life Guards, it was my duty to attend field-days on Worm- 
wood Scrubs. One very hot summer s mornini]^ my horse suddenly 
gave a great shudder, and seemed very much alarmed. At this 
moment I saw a fiy buzzing about ; the fly suddenly darted 
towards the horse's fore-legs, and almost quicker than the eye 
could follow planted a white egg ins^'.de the leg. This informed 
me how the horse gadfly breeds. I examined the egg ; it w^as 
stuck on to the hair by some glutinous material ; the horse 
takes the eggs into his stomach by means of his tongue ; tlicy 
then gradually hatch out into queer-looking grubs, which fasten 
themselves on the sides of the horse's stomach by two hooks 
projecting from the mouth, and imbed themselves into the 
mucous coats of the stomach. I have frequently examined 
these ; the mechanism of the hooks is most beautifuL I 
once found the nostrils of a roedeer entirely blocked up by 
these grubs. It is a very curious thing that the fly never de- 
posits its egg on a part not accessible to the horse's tongue. 
Bluebottle Flies, p. 125. — When I am at woi'k in my dissect- 
ing room the pretty little bluebottles and other flies come to help 
me. It is wonderful liow soon they find out what is going on. 
Though not a bluebottle may be seen about, two or three generally 
arrive in a minute or two. They help me much to make skele- 
tons. 
I once heard of a capital plan to find out the exact IocmU of a 
rat which had been poisoned and had died under the floor of a 
sitting-ioom. A live bluebottle was turned loose ; he hunted 
about the room aaid at last sat down exactly over the spot where 
the dead rat was. He found liim out b\^ the smell. This fly 
