REMEDIES FOR COCKROACHES. G-'> 



often paralyzed by it when not killed outright, and the morning after an ap- 

 plication the infested premises should be gone over and all the dead or 

 partially paralyzed roaches swept up and burned. Flour of sulphur 

 dusted about where roaches abound has proven very effective as a repellent. 



Another remedy which may be used for any of the household species 

 is a mixture of plaster of Paris, one part, and flour, three or four parts, 

 in a saucer, and placed where the roaches abound, with another flat plate 

 nearby, containing pure water, both supplied with several bridges to give 

 easy access, and one or two thin boards floating on the water touching 

 the margin. The insects readily eat the mixture, become thirsty and 

 drink, when the plaster sets and clogs the intestines. The insects disap- 

 pear in a few weeks, the bodies no doubt being eaten by the survivors. 



There are many proprietary substances which claim to be fairly ef- 

 fective roach poisons. The only one of these that has given very satis- 

 factory results is a phosphorous paste, also sold in the form of pills. It 

 consists of sweetened flour paste containing 1 to 2 per cent, of phospho- 

 rus, and is spread on bits of paper or cardboard and placed in the run- 

 ways of the roaches. It is also a repellent. 



For no other insects have so many quack remedies been urged and are 

 so many newspaper remedies published. Many of them have their good 

 points, but the majority are worthless. In fact, rather than put faith in 

 half of those which have been published, it were better to rely on the 

 recipe current among the Mexicans : 



"To GET RID OF COCKROACHES. Catch three and put them in a bottle, 

 and so carry them to where two roads cross. Here hold the bottle upside 

 down, and as they fall out repeat aloud three credos. Then all the cock- 

 roaches in the house from which these three came will go away." 



To the paleontologist interested in tracing back the ancestry 

 of insects, the Blattidae become at once a group of surpassing in- 

 terest, for the oldest known insect is a fossil cockroach, Pahro- 

 l)l<ttt<t douriUci Brogu., from the Silurian sandstone of France. 

 Between 130 and 140 fossil species of the family are known from 

 the Paleozoic rocks of the United States, principally from the 

 Carboniferous formations, but some from all ages as far back as 

 the middle Silurian. That most eminent authority on insect pale- 

 ontology, S. H. Scudder, has written of the cockroach: "Of no 

 other type of insect can it be said that it occurs at every horizon 

 where insects have been found in any numbers; in no group what- 

 ever can the changes wrought by time be so carefully and com- 

 pletely studied as here ; none other has furnished more important 

 evidence concerning the phylogeny of insects." 



The Blattidae are pre-eminently tropical insects, and though 

 abundantly represented in individuals, the number of species in- 

 habiting the United States is comparatively few, but 43 and one 

 variety being treated in Hebard's Monograph of the Group. These 



