Other Stinging Forms—Of the five thousand, or more, species of bees, most possess a sting and poison apparatus and some of the larger forms are capable of inflicting a much more painful sting than that of the common honey-bee. In fact, some, like the bumble bees, possess the advantage that they do not lose the sting from once using it, but are capable of driving it in repeatedly. In the tropics there are found many species of stingless bees but these are noted for their united efforts to drive away intruders by biting. Certain species possess a very irritating saliva which they inject into the wounds.

The ants are not ordinarily regarded as worthy of consideration under the heading of "stinging insects" but as a matter of fact, most of them possess well developed stings and some of them, especially in the tropics, are very justly feared. Even those which lack the sting possess well-developed poison glands and the parts of the entire stinging apparatus, in so far as it is developed in the various species, may readily be homologized with those of the honey-bee.

The ants lacking a sting are those of the subfamily Camponotinæ, which includes the largest of our local species. It is an interesting fact that some of these species possess the largest poison glands and reservoir ([fig. 28]) and it is found that when they attack an enemy they bring the tip of the abdomen forward and spray the poison in such a way that it is introduced into the wound made by the powerful mandibles.

More feared than any of the other Hymenoptera are the hornets and wasps. Of these there are many species, some of which attain a large size and are truly formidable. Phisalix (1897), has made a study of the venom of the common hornet and finds that, like the poison of the honey-bee, it is neither an albuminoid nor an alkaloid. Its toxic properties are destroyed at 120° C. Phisalix also says that the venom is soluble in alcohol. If this be true, it differs in this respect from that of the bee. An interesting phase of the work of Phisalix is that several of her experiments go to show that the venom of hornets acts as a vaccine against that of vipers.

NETTLING INSECTS

So far, we have considered insects which possess poison glands connected with the mouth-parts or a special sting and which actively inject their poison into man. There remain to be considered those insects which possess poisonous hairs or body fluids which, under favorable circumstances, may act as poisons. To the first of these belong primarily the larvæ of certain Lepidoptera.

LEPIDOPTERA