212 Transactions of the [Sess. 



mata, and each sterigma a spore. This number varies in some 

 genera. Besides basidia, there may be noticed at the fructi- 

 ferous surface of Mushrooms projecting cells, round, oval, or elon- 

 gated, which are called cystidia or antheridia. The latter name 

 has been given to them by botanists, who look upon them as 

 organs destined to fertilise the spores and perform the role of 

 anthers in phtenogams. The spores can be seen with the naked 

 eye when they are accumulated in great numbers on the same 

 surface. This is managed by placing the fructiferous surface of 

 a Mushroom on a glass or piece of paper : after some hours lift 

 the plant, and the place will be found stained by a dusty matter 

 entirely composed of spores. Agarics and Boleti leave traces of 

 a very exact drawing of the fruitful surface. It requires millions 

 of these minute bodies to cover the surface of a square inch. 

 Single spores are so small as to escape the sense of touch, but 

 when abundant they have the feeling of fine dust. They are 

 composed of a single very delicate cell containing a fluid holding 

 granulations in suspension. They are oval, elliptic, or spherical 

 in shape, according to the species. In most Mushrooms they are 

 smooth. Whether the envelope of the spore is simple or com- 

 pound is still in doubt. Spores are of various colours, and on 

 this fact Fries founded his jorincipal subdivisions of the Agarics. 

 In the Coprini the young spores are roseate or ashy grey, turn- 

 ing at maturity to a deep black. The gills follow their mode 

 of coloration. The colour of the hymenium, however, is not de- 

 pendent on the spores, several Agarics having the gills coloured 

 and the spores white. Spores of certain species have a peculiar 

 taste and colour. 



Mushrooms have been classed as agamic plants : some botanists, 

 however, assert that they have discovered male and female organs. 

 The cystidia or antheridia — seen only in the higher Fungi — are 

 supposed to be male organs ; but as nothing has been discovered 

 in them resembling either pollen or the liquor contained in the 

 grains of pollen, it is improbable that these bodies are organs of 

 fecundation. They are not arranged like stamens, nor as the spores 

 themselves are in the basidia. They are awanting, too, in a great 

 -many species. "From the researches of Professor Oersted on 

 Agaricus variabilis, it appears," says Carpenter, " that the true 

 generative process in the Agarics and their allies is carried on in 

 the mycelium, and that which has hitherto been considered as their 

 fructification is really a mass of gemmas like the urns in Mosses 

 and the thecaa of Ferns, which are products of the sexual union 

 which takes place in the earlier stages of these plants." It would 

 seem, therefore, that the discovery of the process by which the spore 

 is fertilised remains yet to be made. Germination begins in the 

 sj)ores of some species immediately after quitting the sporophore. 



