THALLOPHYTA— FUNGI 83 



many forms the trichogyne is wanting, and only the coiled por- 

 tion is found. The male organ is sometimes a poUinodium, 

 much like that of the preceding group, and produced in the 

 immediate neighbourhood of the carpogonium. Sometimes it is 

 a filament producing small cells by abstriction. These fila- 

 ments are known as sterigmata, and are borne in special 

 depressed receptacles called spermogonia {figs. 836 and 837). The 

 separate cells correspond to antherozoids, but are incapable of 

 motion and clothed with a cell- wall. They are known as sper- 

 matia. The result of the union of the contents of the poUinodium 

 or spermatium with those of the carpogonium is a fructification 

 called the ascogonium, which is the sporophyte of the fungus. 



In the simplest case, which is that of Eremascus, two hj'phae 

 coil round each other. These correspond to the carpogonium 

 and the poUinodium respectively-. Their contents are said to 

 fuse, and as the result a large globular body is produced at the 

 apex of the coil, the contents of which divide into eight spores. 



In Enrotinm Aspergilhis {fig. 838) a little more difference 

 is found between the two hyphae. The female forms a coil, and 

 from the base of it the poUinodium arises. It becomes closely 

 adpressed to the carpogonium, and fusion of the contents of the 

 two is said to occur. From the base of the carpogonial filament 

 other filaments arise which grow round and envelop it. The 

 coiled carpogonium becomes septated, and from each segment a 

 little protrusion arises which enlarges and becomes an ascus and 

 forms in its interior eight spores. The investment becomes 

 also septated, and forms a thick wall to the whole body. From its 

 ceUs ingrowths arise which graduaUy fill up the spaces between 

 the coils of the carpogonium, forming a solid mass of pseudo- 

 parenchyma. The body so formed is then knoA\'n as the ascogo- 

 nium or ascocarp. From the fact that it remains closed and pro- 

 duces its spores internally, it is sometimes ceiRediOu deistothecium. 



The fungus CoUema, which is generally found in symbiotic 

 relation with an Alga, may be taken as an illustration of another 

 type. The female organ is a septated coiled filament embedded 

 a little below the surface of the organism {fig. 835). Its upper 

 end is prolonged into a tapering filament, the trichogjoie, which 

 projects above the surface. A spermatium liberated from the 

 spermogonium is floated passively to the trichogyne and becomes 

 attached to it. The waUs deliquesce at the point of contact, and 

 fusion of the contents takes place. The trichog^me then withers 

 and the carpogonium develops and pushes its way to the surface, 

 where it expands into a flattened disc which is known as an 



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