The active principle of the seeds has not been satisfactorily isolated. The symptoms suggest the action of a toxalbumin. Teilleux found a resin acid; Louis Astier a volatile alkaloid, and he explains the fact that the seeds, after being heated, are no longer poisonous by the dissipation of this alkaloid.
XIV.—Arum—Bryony—Locust Tree—Male Fern.
§ 619. Arum maculatum, the common cuckoo-pint, flowering in April and May, and frequent in the hedges of this country, is extremely poisonous. Bright red succulent attractive berries are seen on a single stalk, the rest of the plant having rotted away, and these berries are frequently gathered by children and eaten. The poison belongs to the class of acrid irritants, but its real nature remains for investigation.
Some of the species of the same natural order growing in the tropics are far more intensely poisonous.
§ 620. The Black Bryony.—Tamus communis, the black bryony, a common plant by the wayside, flowering in May and June, possesses poisonous berries, which have been known to produce death, with symptoms of gastro-enteritis. In smaller doses the berries are stated to produce paralysis of the lower extremities.[628]
[628] Contagne, Lyon med., xlvi., 1884, 239.