30 PRINCIPAL HOUSEHOLD INSECTS. 



absence of the occupants is undoubtedly due to the development of 

 a brood of fleas in the dust in the cracks of the floor from eggs which 

 have been dropped by some pet dog or cat. This overrunning is 

 more liable to occur in moist than in excessively dry summer weather, 

 and it is more likely to occur during the absence of the occupants of 

 the house, for the reason that the floors do not, under such circum 

 stances, receive their customary sweeping. The use of carpets o.- 

 straw mattings, in our opinion, favors their development under the cir- 

 cumstances above mentioned. The young larvae are so slender and so 

 active that they readily penetrate the interstices of both sorts of cover- 

 ings and find an abiding place in some crack where they are not likely 

 to be disturbed. 



That it is not difficult to destroy this flea in its early stages is shown 

 by the difficulty we have had in rearing it ; but to destroy the adult fleas 

 is another matter. Their extreme activity and great hardiness render 

 any but the most strenuous measures unsuccessful. In such cases we 

 have tried a number of the ordinarily recommended remedies in vain. 

 Even the persistent use of California buhach and other pyrethrum 

 powders, and, what seems still stranger, a free sprinkling of floor mat- 

 ting with benzine, were ineffectual in one particular case of extreme 

 infestation. In fact, it was not until all the floor mattings had been 

 taken up and the floor washed down with hot soapsuds that the flea 

 pest abated. In another case, however, the writer found that a single 

 application of California buhach, freely applied, was perfectly success- 

 ful; and in a third case a single thorough application of benzine also 

 resulted in perfect success. The pyrethrum application was made in a 

 Brooklyn (N. Y.) house, and the benzine application in a Washington 

 residence. The frequently recommended newspaper remedy of placing 

 a piece of raw meat in the center of a piece of sticky flypaper has been 

 thoroughly tried by the writer, without the slightest success. As a 

 palliative measure, however, the plan adopted by Professor Gage in 

 the McGraw Building of Cornell University, and described at length 

 on page 422 of Vol. VII, Insect Life, may be worth trying. It will be 

 remembered that Professor Gage tied sheets of sticky fly paper, with 

 the sticky side out, around the legs of the janitor of the building, who 

 then for several hours walked up and down the floor of the infested 

 room, with the result that all or nearly all of the fleas jumped on his 

 ankles, as they will always do, and were caught by the fly paper. 



In his recent summary of the described fleas (Canadian Entomolo- 

 gist, August, 1895, pp. 221-222) Mr. C. F. Baker shows that there are 

 forty-seven valid species, which attack all sorts of warm-blooded 

 animals. The species which we have just considered (Pulex serrati- 

 ceps Gervais) is, as he states, the common cat and dog flea, well known 

 over all parts of the world. Mr. Baker further states that, "besides 

 the various wild cats and dogs, it has been reported from Herpeses 

 ichneumon (Pharaoh's rat), Fcetorius putorius (common polecat of 



