MR. BORLEY ON THE POISON APPARATUS OF THE WEEYER. 373 
a good supply of venom. This may be the reason for the 
well developed system of capillaries. 
The cells in the portion of the gland nearer its apex are 
different in both form and arrangement. They are roughly 
spherical, arranged in spindle-shaped masses, and the capillary 
blood vessels penetrate between them instead of being, as in 
the basal part of the gland, confined to the capsule or bed of 
the secreting cells. 
The dorsal glands are in the Weevfer unimportant. They 
are said to lie similar in structure to the opercular and are 
situated in pairs, one on each side of a keel which projects 
back from the spines. 
The poison glands of the W'eever are generally considered 
to be modifications of glands of the skin. They much resemble 
sebaceous glands, and glands have been found in the head of 
the Perch which would well represent an intermediate stage 
between the two types of sebaceous gland and venom gland. 
Although poison glands of very similar type have arisen in 
practically all groups of fishes, the group Jugalcs, to which 
the Weever belongs, are especially rich in poisonous fishes, 
and all the species belonging to the genus Trachinus namely 
T. draco, viper a, araneus, and radiatus are armed with poison 
apparatus of the type considered in this note. 
