130 FLOWERLESS PLANTS 



and Hymenomycetes. In the former the spores 

 are developed within the plant and only ex- 

 posed when mature. A tj^pical instance is seen 

 in the case of the Puff Ball. In the latter case 

 the spores, almost from the beginning, are fully 

 exposed. An example of this manner of bear- 

 ing is to be seen in the case of the Common 

 Mushroom, where the httle stalks bearing the 

 spores are present on the gills. The Ascomycetes 

 are also divided into sub-orders — Pyrenomycetes 

 and Discomycetes. In the first instance the 

 spore-bearing surface is enclosed in a bottle- 

 shaped body, whilst in the latter case the posi- 

 tion of the spore-producing cells is much more 

 exposed. It may be said that, apart from a 

 few common examples which are almost certain 

 to be met with, a huge number of the Asco- 

 mycetes are very small, and could only be 

 studied satisfactorily with the aid of a micro- 

 scope. 



Under the sub-order Hymenomycetes are 

 included some of the most interesting of fami- 

 lies. Most familiar of all are the Agarics, 

 two famihar types of which are the Succulent 

 Mushroom {Agaricus campestris) and the highly 

 poisonous, though most attractive. Fly Agaric 



