I have easily succeeded in vaccinating mice against doses of bee-venom certainly lethal, by repeatedly inoculating them with very small doses. Moreover, we find the same thing in the case of human beings, for we know that those who are in the habit of handling hives become quite accustomed to bee-stings, and finally feel not the slightest effect from them.
It has been shown by J. Morgenroth and U. Carpi,[133] in a paper recently published, that the venom of bees, like that of the scorpion, possesses the property of hæmolysing the red corpuscles of several species of animals (the rabbit, guinea-pig, and goat), and that it is capable of combining with the lecithin to form a lecithide analogous to cobra-lecithide, the curious properties of which we have studied in detail.
This lecithide of bee-venom is from 200 to 500 times more hæmolysing than the venom itself, and resists ebullition like that of the cobra. In order to isolate it Morgenroth and Carpi employed the method recommended by P. Kyes: 1½ c.c. of a solution of pure venom is mixed with 1½ c.c. of a 5 per cent. solution of lecithin in methylic alcohol. After being kept for twenty-four hours at 37° C., 22 c.c. of absolute alcohol are added; the liquid is decanted, and the clear filtrate is mixed with 150 c.c. of ether. There is slowly formed a somewhat copious flocculent deposit, which is collected on a filter, washed several times with ether, and finally dried. The lecithide that remains on the filter dissolves completely in physiological salt solution.
It must be remarked that bee-venom, without the addition of lecithin, gives a scanty precipitate with ether. This precipitate, dissolved in physiological salt solution, possesses no hæmolysing power. The lecithide, on the contrary, dissolves red corpuscles almost instantaneously.
Normal horse-serum considerably inhibits hæmolysis by bee-venom + lecithin. This protective action of normal serums has already been observed by Langer; it is perhaps attributable to the cholesterin that they contain.
Among other Hymenoptera capable of inflicting very severe stings may be mentioned the species of Polistes and certain Pompilids, especially a species of Pompilus found in Natal, the painful stings of which have sometimes been experienced and described by travellers (P. Fabre, of Commentry).[134]
In the family Crabronidæ the females are provided with a sting and venom, which usually has little effect upon man, but is toxic to other insects. Thus, Cerceris bupresticida is remarkable for the stupefying effect of its venom upon the Buprestidæ destined for the food of its larvæ. It stings the beetles between the first and second segments of the thorax, with the result that the victim is paralysed, though in other respects its bodily functions appear to continue; in fact, its intestine is seen to empty itself at long intervals. These effects are attributed by Mons. J. H. Fabre, of Avignon, to the direct action of the venom upon the ganglia of the thoracic nervous system.
Instances of Hymenoptera belonging to the tribe Entomophaga actually depositing their eggs beneath the skin of man are mentioned by Raphaël Blanchard.[135]
According to P. Fabre, the best treatment for wasp- or bee-stings would appear to consist in the application of strong saline solution, or a liniment of ammonia and olive oil. For my own part, I have tried hypochlorite of lime, in a 1 in 60 solution, or eau de Javel diluted to 1 per cent., and have always obtained such excellent results from these remedies that I do not hesitate to advise their use.