=Poison of Spiders.=—All spiders possess poison-glands, which have their openings on the fangs of the chelicerae. The action of the chelicera in striking does not express the venom, but the poison-bag itself is covered with a muscular coat by which the contained fluid is expelled. It is highly probable, therefore, that the venom is under the control of the animal’s will, and is economised when the simple wound is sufficient for the purpose—a supposition which may partially explain the very divergent opinions held with regard to the effect of the spider’s bite. The reputation of the “Tarantula” Spider is well known, but what particular species, if any, was intended by the name is quite uncertain. The name is derived from the town Tarentum, and was certainly applied to a Lycosid spider. Probably the common south European species, _Lycosa narbonensis_, has as good a claim to the honour as any. The confusion has been increased by extending the name to spiders of quite a different family. _Eurypelma hentzii_, one of the Aviculariidae, is commonly known as the Tarantula in America. The superstition of the tarantula dance is well known. The bite of the spider was supposed to induce a species of madness which found its expression—and its cure—in frantic and extravagant contortions of the body. If the dance was not sufficiently frenzied, death ensued. In the case of survivors, the symptoms were said to recur on the anniversary of the bite. Particular descriptions of music were supposed to incite the patient to the excessive exertion necessary for his relief; hence the “Tarantella.” In the Middle Ages epidemics of “tarantism” were of frequent occurrence, and spread with alarming rapidity. They were seizures of an hysterical character, analogous to the ancient Bacchic dances, and quite unconnected with the venom of the spider from which they took their name. The condition of exaltation and frenzy was contagious, and would run through whole districts, with its subsequent relapse to a state of utter prostration and exhaustion. The evil reputation of the Tarantula appears to have exceedingly little basis in fact. Baglivi relates how the country people capture the Tarantula by imitating the buzzing of an insect at the mouth of its hole. “_Quo audito, ferox exit Tarentula ut muscas, quorum murmur esse putat, captet; captatur tamen a rustico insidiatore._”