The accessory poison-gland, which is lanceolate or ovoid in shape, consists of a small, granular mass, the extremely narrow excretory duct of which opens at almost the same point as that of the alkaline gland. It does not exist in all Hymenoptera. The stings of hive bees (_Apis mellifica_), wasps (_Vespa vulgaris_), violet carpenter bees (_Xylocopa violacea_), and humble bees (_Bombus lapidarius_) cause considerable discomfort. The venom of the carpenter bee, which is of some strength, has been studied by P. Bert, and I have myself made experiments with that of the hive bee (_A. mellifica_). The venom extracted from a couple of bees, by crushing the posterior extremity of the body in 1 c.c. of water, is sufficient to kill a mouse or a sparrow. Death supervenes in a few minutes, from respiratory asphyxia, as in the case of intoxication by the venom of Colubrine snakes (_Cobra_). In the blood-vessels and in the heart the blood is black and remains fluid. It therefore appears that this venom contains a very active _neurotoxin_. The phenomena of intoxication caused by the venom of these insects are, as a rule, slight, being limited to an acute pain, accompanied by a zone of œdema and burning itching. Sometimes however, when the stings are in the eyelids, lips, or tongue, they produce alarming and even fatal results, as shown by the following incident:-- On September 26, 1890, a young girl of Ville-d’Avray was eating grapes in the woods of Fausse-Repose, when she inadvertently swallowed a wasp. The unfortunate girl was stung in the back of the throat, and the wound became so rapidly inflamed that, in spite of the attentions of a doctor, she died in an hour from suffocation, in the arms of her friends. Phisalix[131] has studied the physiological action of bee-venom on sparrows inoculated either by the sting of the insect, or with an aqueous solution obtained by crushing the glands. In both cases a local effect, paralysis of the part inoculated, is first produced; this is followed by convulsions, which may last for several hours; the final stage is marked by coma and respiratory trouble, which ends in death. After being heated for fifteen minutes at 100° C. the venom has no further local action; the general phenomena are merely diminished. If heated at 100° C. for thirty minutes, the venom ceases to cause convulsions, but remains stupefactive. Exposure for fifteen minutes to a temperature of 150° C. renders it completely inert. This venom therefore comprises: (1) A phlogogenic substance, destroyed by ebullition, contained in the acid gland of the bee; (2) a poison causing convulsions, which does not resist a temperature of 100° C., if prolonged, and is probably produced by the alkaline gland; (3) a stupefactive poison, which is secreted by the acid gland, and is not entirely destroyed until a temperature of 150° C. is reached. The poison-glands can easily be extracted by gently pulling at the stings of bees anæsthetised by chloroform.