1942: Entomology

Samson R. Dutky of Moorestown, N. J., has described two micro-organisms, Bacillus popilliae and Bacillus lentimorbus which are found in the blood of larvae beetles having milky disease. A plentiful supply of these bacteria can be obtained and possibly used against future invasions of the Japanese beetle by separating the spores from dried blood and reinjecting them into healthy larvae and thus maintaining a constant increasing supply.

Dr. A. A. Nikitin, of the Tennessee Copper Company, has reported a method whereby many kinds of enemy insects can be exterminated with dusts containing talc or fine clay which is obtained from the soil in Georgia and other southeastern states. This material, he reports, can be combined with poisonous chemicals and hence reduces the cost. Even without the addition of poisonous compounds the white dust is reported to repel many kinds of insect pests.

Dr. J. C. Cross of Texas College of Arts and Industries, Kingsville, Tex., has reported a very simple method of controlling termites. He has used his own home for the experiment and has poured discarded lubricating oil into little ditches which surround the concrete piers in the foundation. He states that the oil stays in the ground for a considerable time and does not diffuse more than a few inches from the ditches. Hence the growth of shrubs six inches distant are not affected by the oil.

A new insecticide known as Thanite and derived from Southern pine has been found to be a suitable substitute for pyrethrum and rotenone in fly-killing sprays for use in homes and dairy barns. This substance is said to be effective against mosquitoes, moths, spiders, ants, mites, bedbugs and roaches. This chemical substance, known as the thiocyanoacetate of a secondary terpene alcohol was discovered by chemists of the Hercules Powder Company and bids fair promise of further increasing American independence of war-pinched imports.

Dr. J. W. Zukel of the Department of Zoology and Entomology at Iowa State College has investigated the effect of an organic compound, known as phenothiazine, upon the American cockroach. It was found that this substance was toxic to the roach by acting entirely by contact with the body surface. No toxic effects resulted when the chemical was taken into the alimentary canal.

Investigators at the University of New Hampshire report the discovery of a new fumigant for grain and flour. It is highly penetrating and extremely deadly to insects but harmless to humans. It is known as chlorinated nitro-ethane. The chemical is a clear liquid and evaporates readily upon exposure to air. The fumes penetrate rapidly into large masses of flour or grain, hence the simple method of merely placing the chemical on top of the grain in a closed car could readily be utilized for practical purposes.

Entomologists of the U. S. Department of Agriculture report on the number of insect enemies of the guayule plant which it is hoped can be utilized in relieving the rubber shortage in this country. They have found that the most destructive insect is the bark beetle which attacks the plant after harvesting. To date this beetle is only reported in Mexico but may eventually serve as a menace in the United States at a later date unless controlled. Other potential insect enemies of the guayule plant which are being studied are the root-eating white grubs, caterpillars, grasshoppers, mites, leafhoppers, and wireworms.

Investigators at Iowa State College have made a study of the life histories and reproduction habits of the American cockroach, and have shown experimentally that a female roach may raise on the average as many as one hundred sixty-three offspring during an adult lifetime of less than one year. It was also found that in some cases reproduction could occur in unmated females while in other cases some individuals continued to reproduce offspring from several months to a year following a single mating.

Dr. W. A. Dreyer of the University of Cincinnati has made some interesting studies on the life span of the common ant-hills as found in Northern Illinois. He reports the average life span for such a community is from fifteen to twenty years with definite cycles during this period when they grow, flourish, decline, and finally die.

Dr. S. D. Griffitts, of the School of Tropical Medicine at San Juan, Puerto Rico, reports that experiments have shown that ants, usually considered harmless insects, may be guilty of spreading dysentery. Dr. Griffitts has shown by experiments that ants could carry dysentery germs on their feet at least twenty-four hours after walking across material containing the germs.

The puss caterpillar, known technically as Megalopyge opercularis has been reported guilty of poisoning individuals. Dr. T. L. Lucas, of the Walter Reed General Hospital, Washington, D. C., has reported a case in a recent issue of a medical journal. The author believes other cases no doubt occur frequently but are not reported for some reason. The poison was reported serious but not fatal. This puss caterpillar is widely distributed in the Southeastern United States, and is found on elm, plum, sycamore, and oak trees as well as in orchards and on corn.

Dr. A. B. Sabin and Robert Ward of the Children's Hospital Research Foundation and the Department of Pediatrics of the University of Cincinnati College of Medicine have continued and expanded their experiments to show the possible role of insects in the epidemiology of poliomyelitis. They have distinctly shown that flies of a number of species are carriers of the virus. However, as they state, the search for a reservoir of poliomyelitis virus among lower animals should still be continued.