13 



REMEDIES. 



Like the crows among birds, the roaches among insects are appar- 

 ently unusually well endowed with the ability to guard themselves 

 against enemies, displaying great intelligence in keeping out of the 

 way of the irate housekeeper and in avoiding food or other substances 

 which have been doctored with poisons for their benefit. Their 

 keenness in this direction is unquestionably the inheritance of many 

 centuries during which the hand of man has ever been raised against 

 them. 



A thoroughly effective and simple means of ridding one's premi- 

 ses of roaches has been found, however, and is in fumigating with 

 hydrocyanic-acid gas. The experience of the last year or two has 

 demonstrated that this gas, formerly employed for disinfecting nurs- 

 ery stock and orchard trees (notably, citrus) from scale and other 

 insects, is equally effective against household insects, and is particu- 

 larly applicable and satisfactory against all species of house roaches. 

 The gas is extremely poisonous to human beings, but with the 

 proper precautions, may be emploj^ed with complete safety. A 

 special circular (No. 4G of this series) has been prepared by Dr. 

 Howard, giving the steps of the process in detail. 



The means formerl}^ employed against cockroaches, detailed below, 

 are of value, however, and will be in order where fumigation maj^ 

 be deemed undesirable or is impracticable. 



Poisons and 7'epellents. — As just noted, roaches often seem to 

 display a knowledge of the presence of poisons in food, and, not- 

 withstanding their practically omnivorous habits, a very little 

 arsenic in baits seems to be readily detected by them. In attempt- 

 ing to eradicate roaches from the Department storerooms where 

 cloth bound books are kept various paste mixtures containing 

 arsenic were tried, but the roaches invariably refused to feed on 

 them in the least. This applies particularly ^o the German roach, 

 or Croton bug, and may not hold so strongly with the less wary and 

 perhaps less intelligent larger roaches. 



A common remedy suggested for roaches consists in the liberal 

 use of pyrethrum powder or buhach, and when this is presisted in 

 considerable relief will be gained. It is not a perfect remedy, how- 

 ever, and is at best but a temporary expedient, while it has the 

 additional disadvantage of soiling the shelves or other objects over 

 which it is dusted. When used it should be fresh and liberally 

 applied. Roaches are often paralyzed by it when not killed out- 

 right, and the morning after an application the infested premises 

 should be gone over and all dead or partially paralyzed roaches 

 swept up and burned. Flowers of sulphur dusted about where 

 roaches abound has proved on the authoritj^ of Mr. A. I. Mudd, of 

 this Department, very effective as a repellent. 



