SUMMER MEETING. 



85 



looked for where they really are, they will prohably pass unobserved because 

 most of them are too small to be detected by the unaided eye. 



It is by their works that we most often know them, and to the student of 

 natural science who has time and facilities to devote to careful microscopic 

 study must we look for most of the needed information concerning them. 

 Some species, however, as the common wood ticks or large red mites of the 

 garden, are of a size to be readily seen. 



Less than a year ago a lady sent to the 

 laboratory a sample of her graham flour 

 which she said was infested with mites. A 

 microscopical examination of the flour 

 brought to light a large number of two spe- 

 cies of mites, one of which must have been 

 entirely invisible to any person who did not 

 possess the keenest eyesight. The other is 

 represented in Fig. 1 highly magnified. 

 There is not one housewife in a thousand 

 who would not have gone on making her 

 bread of this inhabited flour entirely un- 

 aware that every loaf would have entombed 

 withiti it hundreds of these minute animals 

 which, under the microscope, look so much 

 like the great ugly spider that women are 

 so disposed to stamp upon. "But where 

 ignorance is bliss it is folly to be wise " and 

 I do not know that well cooked mites would 

 prove unwholesome food. The neat, ener- 

 getic housewife would certainly rather be to 



the trouble of frequently scalding and refilling her flour box than to know she 



was setting before her family bread that contained these repulsive looking 



animals. 



Mites are not found in flour alone but, notably, in the cheese and sugar of 



the groceryman, and in the skin of uncleanly persons, caus- 

 ing the loathsome diseases known as itch and jiggers. The 



diseases known as mange in lower animals are produced by 



skin burrowing mites very similar to the one producing 



itch in man. Many of our most cherished trees and 



shrubs often have their foliage almost entirely destroyed 



either for beauty or for performing its natural function 



in the economy of plant life by exceedingly small mites that 



produce warty or teat-like excrescences upon the surface of 



the leaves. In fact there are a thousand and one differ- 

 ent ways by which these little creatures affect more or 



less directly our comfort and happiness and I offer no 



other excuse for appearing before you with the subject in 



hand. 



One who has never made entomology a study would 



probably call the mites little microscopic insects. Scientists 



ha^e seen fit to separate mites and spiders into a group 



(Arachinda) by themselves. All insects have their bodies 



divided into three parts, head, thorax, and abdomen, and Fig- 2. 



Fig. 1. 



Chyletus in Flour. 



