THE POPULAR SCIENCE MONTHLY.
prefer having their corners cleaned in the ordinary way, with soap and water; nevertheless, it is sometimes of service in this way. This cockroach is of a dark-brown color, about an inch in length; the male having short wings, while the female has only rudimentary wings. It is very troublesome in kitchens, coming out at night when the lights are out.
A somewhat larger insect is the American cockroach (Periplaneta americana), which is a lighter brown color, both the male and female having well-developed wings. This species is not so often found in houses, but frequents water-pipes and sewers and the cargoes of vessels.
The smallest cockroach which is a pest in our houses is the "water-bug" (Ectobia lapponica). It is also known as the "Croton-bug." This insect is very common in houses in New England, and, though eating any kind of food, is especially fond of bread. It frequents bakeries, where it proves a great annoyance, sometimes being baked in the bread in spite of care. It also eats the covers of books bound in cloth, but will not touch those bound in leather.
It has been said that sailors have been greatly troubled by cockroaches eating the nails of their fingers and toes, and the hard parts of their feet and hands, but this has been questioned. However, a writer in Nature affirms that while in Australia he was awakened one night by cockroaches nibbling his feet, which were badly blistered, and in the morning he found the skin had been eaten from a large blister, causing a painful sore, and that the hard skin of the heel had also been eaten. Another writer in the same journal says that this habit of cockroaches is well known to all West Indians.
Borax is very disagreeable to cockroaches and will drive them away, and it is said to kill them if mixed with white sugar and sprinkled around the corners frequented by them. The following receipt for a preparation to exterminate cockroaches is given in a late number of Science: thirty-seven parts of borax, nine parts of starch, and four parts of cocoa. This preparation should be sprinkled around their haunts.
Insect-powder does not kill them but renders them stupid, and while in this condition they can easily be swept up and destroyed. In England cockroaches are sometimes caught with stale beer, which is placed in a deep dish, bits of wood being so arranged that the cockroaches can climb into the liquid. The following preparations are mentioned in Harris's Insects Injurious to Vegetation, but, as they are poisonous, they should be used with the greatest care. The first is a tablespoonful of red lead and Indian meal, mixed with enough molasses to make a thick batter; the other is a teaspoonful of powdered arsenic mixed with a table-