Handbook of medical entomology . rrow neck of the resen^oir. The poison is usually referred to as formic acid. That it is not soeasily explained has been repeatedly shown and is evidenced by thepresence of the two types of glands. Carlet maintains that the pro-duct of either gland is in itself innocent,—it is only when they are combined thatthe toxic properties appear. The most detailed study of the poisonof the honey-bee is that of Josef Langer(1897), who in the course of his work usedsome 25,000 bees. Various methods ofobtaining the active poison for experi-mental purposes were used. For obt
Handbook of medical entomology . rrow neck of the resen^oir. The poison is usually referred to as formic acid. That it is not soeasily explained has been repeatedly shown and is evidenced by thepresence of the two types of glands. Carlet maintains that the pro-duct of either gland is in itself innocent,—it is only when they are combined thatthe toxic properties appear. The most detailed study of the poisonof the honey-bee is that of Josef Langer(1897), who in the course of his work usedsome 25,000 bees. Various methods ofobtaining the active poison for experi-mental purposes were used. For obtainingthe pure secretion, bees were held in thefingers and compressed imtil the sting wasexserted, when a clear drop of the poisonwas visible at its tip. This was then takenup in a capillary tube or dilute solutionsobtained by dipping the tip of the sting intoa definite amotmt of distilled aqueous solution of the poison was more readily obtained bypulling out the sting and poison sacs by means of forceps, and grinding. Poison apparatus of a honeybee. Modified from Snod-grass. 38 Poisonous Arthropods them up in water. The somewhat clouded fluid was then filteredone or more times. For obtaining still greater quantities, advantagewas taken of the fact that while alcohol coagulates the poison, theactive principle remains soluble in water. Hence the stings withthe annexed glands where collected in 96 per cent alcohol, afterfiltering off of the alcohol were dried at 40° C, then rubbed to a finepowder and this was repeatedly extracted with water. Throughfiltering of this aqueous extract there was obtained a yellowish-brown fluid which produced the typical reactions, according to con-centration of the poison. The freshly expelled drop of poison is limpid, of distinct acidreaction, tastes bitter and has a delicate aromatic odor. On evapora-tion, it leaves a sticky residue, which at 100 degrees becomes fissured,and suggests dried gum arabic. The poison is readily soluble inwa
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectinsectp, bookyear1915
