_PHYSIOLOGY OF POISONING_ (_continued_). EFFECTS OF THE VARIOUS VENOMS ON THE DIFFERENT TISSUES OF THE ORGANISM. The physiological effects of the various venoms are very different from those that we have just described, when these toxic substances are introduced into the organism otherwise than subcutaneously. Their direct penetration into the blood-stream, whether by the bite of the snake itself or by experimental intravenous injection, always produces immediate results. With the venoms of VIPERIDÆ, coagulation of the blood and, consequently, death are almost instantaneous. With the venoms of COLUBRIDÆ, which, on the contrary, destroy the coagulability of the blood, the toxic effects are less rapid, but after the lapse of only a few minutes asphyxia ensues and the death-struggle is very short. Absorption by the serous membranes is slower, but is nevertheless effected much more quickly than when it takes place in the subcutaneous cellular tissue. When cobra-venom is injected into the peritoneal cavity of a rabbit or a guinea-pig, the local effects upon the serous membrane are almost _nil_. No leucocytic exudation is observed; death supervenes before this has had time to take place. The venoms of VIPERIDÆ, on the contrary, produce, directly after their introduction into the peritoneum, an enormous afflux of sanguinolent serosity; the capillary vessels of the serous membrane, immediately becoming distended, allow the blood to filter through their walls, and the animal succumbs after a few minutes, or a few hours, according to the dose injected, with the peritoneum full of blood. When deposited upon the mucous membranes of the eye, vagina, or urethra, all venoms, those of COLUBRIDÆ like those of VIPERIDÆ--but the latter with greater intensity--cause very acute inflammation, comparable to that produced by jequirity; the capillaries become distended, allow leucocytes to exude _en masse_, and, as for instance upon the eye of the rabbit, a purulent ophthalmia soon establishes itself. Certain species of _Sepedon_ (COLUBRIDÆ), common on the West Coast of Africa, especially in Senegambia and in the hinterland of Dahomey, and to which the name _Spitting Snakes_ has been given, possess the faculty of projecting little drops of venom to a distance by forcibly expelling the air from their lungs, and the natives assert that this venom, when it happens to come into contact with the eyes, causes blindness. This is true to a certain extent, in so far as it produces attacks of purulent ophthalmia which are often serious; but these attacks, like those provoked experimentally in animals, can be cured in a few days when properly treated.