GARPOPETTA. 155 



alcohol or glycerine. However, much may be made out by the care- 

 ful examination of dried specimens. 



Red Seaweeds may often be obtained " in the rough" which can 

 be sliglitly moistened and then pressed out and dried for study. 

 Such material will often yield quite good specimens. 



Good mounted microscopic specimens may sometimes be obtained 

 showing the structure of the plant as well as of the sexual and asex- 

 ual reproductive organs. 



Class m. Ascomtcbtes (the Sac-Fungi), 



320. This large class includes chlorophyll-less plants 

 which differ much in size and appearance, hut which agree 

 in producing their fruit-spores (sac-spores, or ascospores) 

 in sacs (asci). 



321. The sexual organs consist of carpogones and anther- 

 ids, and, after fertilization, produce a spore-fruit (sporo- 

 carp) which includes the sacs and their contained sac-spores. 

 The most common number of sac-spores is eight in each 

 sac; hut it sometimes exceeds, and frequently falls short, of 

 this number, there being often no more than one or two. 

 The sacs are in many cases arranged side by side in a com- 

 pact mass, forming a spore-bearing surface (the hymenium). 



322. In addition to the sac-spores there are generally one 

 or more other kinds of spores which are developed asexu- 

 ally. Some of these are doubtless to be regarded as the 

 equivalents of the conidia of the lower groups, and will 

 accordingly be so named here. 



Of the Sac-fungi there are a number of well-marked 

 orders, all but one of which are popularly known as fungi. 



323. The Blights %nd their Allies [Order Perisporia- 

 cece). — These plants, which are mainly parasitic, are com- 

 posed of branching jointed filaments (hyphce) which form 

 a white web-like film upon the surface of the leaves and 

 stems of their hosts. There are both sexual and asexual 



