Febeuaby 17, 1899.] 



SCIENCE. 



237 



makes use of the following words : " Gen- 

 eral Washington told me that he never was 

 so much annoyed by mosquitoes in any 

 part of America as in Skenesborough, for 

 that they used to bite through the thickest 

 boot." Now, knowing that the boots of 

 those days were very thick and that the 

 mosquitoes of that time must have been 

 structurally identical with those of to-day, 

 there arises instantly a question of veracity 

 between Mr. Weld and General Washing- 

 ton ; and as we know from Dr. Weems' 

 veracious history that General Washington 

 was so constituted that he could not tell a 

 lie, it looks very much as though Mr. Weld, 

 like many another English traveller who 

 has written a book on his retm-n home, has 

 been inclined to overstate the truth. 



In these days of comparative personal 

 cleanliness some of the most disgusting of 

 the insect annoyers of man have dropped out 

 of sight. The lice, which in former days 

 were common in all classes of society, from 

 king to peasant, are now comparatively un- 

 known. The itch disease, which carried off 

 many a famous character in history, is 

 equally rare. That it still persists, how- 

 ever, is shown by an occasional case re- 

 ported in medical journals. For example, 

 Dr. Eobert Hessler, of Indianapolis, re- 

 ported in 1892 a case in his own practice 

 of typical Norway itch in which the itch 

 mites were present in the skin of the patient 

 in enormous numbers. A rough estimate 

 showed seven million eggs and two million 

 mites. 



Those of us who live in a reasonably civil- 

 ized way are confined, in our experience of 

 annoying insects, largely to the forms men- 

 tioned in our opening paragraph, namely, 

 mosquitoes and house flies and rarely fleas ; 

 but a glance through the medical literature 

 reveals the existence of more or less fre- 

 quent cases of such a nature that they are 

 little less than horrible. Promineut among 

 these are the cases of so-called Myasis, and 



especially those resulting from the attacks 

 of the screw worm fly, Compsoviyia macel- 

 laria. 



Residents of temperate regions are fortu- 

 nate as compared with those of tropical 

 regions in respect to the personally annoy- 

 ing insects. Our troubles from these indi- 

 vidually insignificant causes are intensified 

 to a degree in warmer countries, where the 

 comfort of the individual absolutely depends 

 upon the adoption of measures, always dif- 

 ficult and frequently impracticable, to ex- 

 clude insects from his person and from his 

 food. This is so well known in these days 

 of numerous books of travel that I will 

 close this aspect of our question simply 

 with a quotation from a poet of the Indies, 

 written many years ago : 



" On every dish the booming beetle falls, 



The cockroach plays, or caterpillar crawls : 



A thousand shapes of variegated hues 



Parade the table and inspect the stews. 



To living walls the swarming hundreds stick. 



Or court, a dainty meal, the oily wick ; 



Heaps over heaps their slimy bodies drench, 



Out go the lamps with suffocating stench. 



When hideous insects every plate defile, 



The laugh how empty, and how forced the smile !" 



AS CAEEIERS OF DISEASE. 



Manson's demonstrated transmission of 

 the filaria diseases of the East (elephan- 

 tiasis, chyluria and lymph scrotum) by in- 

 sects ; the discovery by Salmon and Smith 

 of the carriage of the germ of Texas fever 

 by the well-known Southern cattle tick ; 

 the discovery by Koch of the fact that the 

 Tsetse fly of Africa is so destructive to 

 animals, not by its bite alone, but by carry- 

 ing into the circulation of the animal that 

 it attacks the micro-organisms of disease ; 

 the demonstration by Howe and others of 

 the previously suspected fact that the puru- 

 lent conjunctivitis of the Egyptians is spread 

 by the house fly ; the partly proven hypoth- 

 esis of Manson and Grassi of the relation 

 existing between mosquitoes and malaria ; 

 the circumstantially proven carriage of the 



