OllTHOPTEHA OF INDIANA. 191 



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

 Eoaches are often paralyzed by it when not killed outright, and the 

 morning after an application 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. 



"There are many proprietary substances which claim to be fairly 

 effective roach poisons. The usefulness of most of these is, however, 

 very problematical, and disappointment will ordinarily follow their 

 application. The only one of these that has given very satisfactory 

 results is a phosphorus paste, also sold in the form of pills. It con- 

 sists 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 

 runways of the roaches. It has been used very successfully in the 

 Department to free desks from Croton bugs, numbers of the dead 

 insects being found in the drawers every day during the time the 

 poison was kept about. 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 which T. A. Janvier gives (in his charm- 

 ing article on "Mexican Superstitions and Folk-lore," published in a 

 recent number of Scribner's Magazine) as current among the Mexi- 

 cans: 



"To Get Rid of Cochroaches. — 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 cockroaches in the house from which these three came will go 

 away." 



Sub-family PERIPLANETIN.^D. 



The two Indiana members of this sub-family are our largest 

 roaches. Both are introduced species which have become thor- 

 oughly naturalized, and one of them is better kno^m than any of our 

 indigenous or native forms. The main distinguishing character of 

 the sub-family is that pertaining to the last ventral segment of the 

 female, which is keeled or boat-shaped, and divided into two valves. 

 The head is large, flattened or slightly concave and not wholly cov- 

 ered by the pronotum. The antennae are setaceous, more or less 

 pubescent, the joints obconic and very short. The tegmina and wings 

 are variable in the different species, being fully developed, abbre- 



