[Illustration: Plate XVI. Fig. 1. Ag. (Amanita) vernus, Bull. (Amanita verna.) "Spring Mushroom." Fig. 2. Represents section of mature plant. Fig. 3. Spores; Fig. 4. Young plant. POISONOUS. T. Taylor, del.] PLATE XVI. FIGS. 1 to 4.--=Ag. (Amanita) vernus= Bull. =(Amanita verna)= Linn., =Amanita bulbosa=, =Ag. solitarius.= "_Vernal Mushroom_," "_Spring Mushroom_," etc. POISONOUS. Cap at first ovate, then expanded, becoming at length slightly depressed, viscid, white; margin smooth; flesh white; gills white, free; stem white, equal, stuffed or hollow, easily splitting, floccose, with bulbous base; volva white, closely embracing the stem, but free from it at the margin; ring reflexed; spores globose, .0003 in. broad. The plant is creamy white throughout and does not seem to be easily distinguishable from the white forms of A. _phalloides_. Fries and some others consider this species merely a variety of Amanita _phalloides_, and it is regarded as equally poisonous, the poisonous principle being the same as that of A. _phalloides_. It is very common in mixed woods from early spring to frosty weather. ALKALOIDS OF THE POISONOUS MUSHROOMS. Schrader, after some experiments made in 1811, stated that the poisonous principle of the "Fly mushroom," Amanita muscaria, seemed to be combined with its red coloring matter and might be extracted by water or aqueous alcohol, but that it was not soluble in ether. Vaquelin, as the result of more extended investigations made in 1813, expressed the opinion that this poison was not confined to the coloring matter of the mushroom, but that it was an integral part of the fatty constituents not only of _muscaria_ but of several species of mushrooms. In 1826 and 1830, and again in 1867, important investigations were made and published by Letellier relating to the medical and poisonous properties of mushrooms growing around Paris. Letellier's early investigations led him to the conclusion that there were two poisons contained in certain fungi--(1) an acrid principle easily destroyed by drying or boiling or by maceration in alcohol or in alkaline solution, and (2) a peculiar poisonous alkaloid found only in certain of the Amanita group. Letellier in 1866 named this latter alkaloid _amanitin_. He then considered it to be the active poison of Amanita _muscaria_, Amanita _phalloides_, and Amanita _verna_, but a subsequent analysis by the German chemists Schmiedeberg and Koppe showed the _amanitin_ of Letellier to be identical with _cholin_, a substance found in bile. Kobert says that _amanitin_ is non-poisonous in itself, but states that it may be changed on decay of the mushroom to the muscarin-like acting _neurin_, which is highly poisonous. He thinks it highly probable that nearly all of the edible and non-edible mushrooms contain pure _amanitin_ (cholin) partly in primitive condition and partly in a more intricate organic connection, as _lecithin_.