282 
VENOMS 
Janet," and Seurat,’ always include two and sometimes three kinds 
of glands: the acid gland, the alkaline gland or gland of Dufour, 
and the accessory poison-gland (fig. 99). 
Fia. 100. —INTERIOR OF 
THE GORGET OF THE BER, 
SEEN FROM ITS POSTERIOR 
ASPECT, 
cv, Poison chamber; gor, 
gorget ; st, stylet; ca, 
piston. Between the two 
stylets is seen the cleft fa, 
by which the air is able 
to enter into the air- 
chamber cai. 
(After Carlet: figure bor- 
rowed from Hommel.) 
fort. 
The acid gland comprises a glandular 
portion (which sometimes takes the shape 
of a long flexuous tube, always bifid at its 
extremity, sometimes that of two tubes, 
simple or ramified, or again is composed of 
a bundle of cylindrical, simple or multifid 
canals), à poison-sac or reservoir, ovoid or 
spherical in shape, and an excretory duct, 
which is usually short. 
The alkaline gland, or gland of Dufour, 
exists in all Hymenoptera, and presents the 
appearance of an irregular tube, with a 
striated surface and a spherical or conical 
upper extremity. Its excretory duct opens, 
beside that of the acid gland, at the enlarged 
base of the gorget of the sting (fig. 100). 
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 (Bom- 
bus lapidarius) cause considerable discom- 
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 
' Comptes rendus de l'Académie des Sciences, 1898. 
* Annales sc. Anat. Zoologie, 8e série, t. x., 1898. 
