156 



PRACTICAL BOTANY. 



the yellow color distinctly visible to the naked eye. Draw 

 a typical spore fruit. By pressure on the cover glass burst 

 some of the spore fruits and study the ascospores. Eight 



ascospores are 

 borne in each 

 sac. Find as 

 many as possible 

 of the stages 

 in the develop- 

 ment of the spore 

 fruit. The be- 

 ginning of the 

 development is 

 by the out- 

 growth of a 

 spirally coiled 

 branch which 

 becomes the as- 

 cogonium. From 

 just beneath this 

 another branch, 

 the pollinodium, 

 rises, extending 

 to the top of 

 the ascogonium. 



FIG. 88. Eurotium repens. A, a portion of the 

 mycelium bearing at st a gonidiophore, and at as a 

 young ascogonium ; B and C show the ascogonium 

 more advanced and enveloped in the pollinodium 

 p ; ZHs a fully matured ascogonium ; E and F are 

 sections through a young ascogonium ; G is one of 

 the asci or sacs that are borne in the ascogonium, 

 and H is one of the ascospores which are borne in 

 the ascus. (After Goebel.) See Fig. 86, 4 and 5. 



It is supposed, 

 though this fact has not been proved, that the pollinodium 

 fertilizes the ascogonium. The ascogonium becomes en- 

 veloped in other branches which start from below its base 

 and tightly inclose it. The mature ascogonium bears 

 several sacs, each containing eight ascospores. 



References for Reading. Bennett and Murray's "Cryptogamic 

 Botany," pp. 364-366 ; Huxley and Martin's "Practical Biology," pp. 

 419-427; Bower's "Practical Botany," pp. 484-490; Goebel's "Classi- 

 fication of Plants," pp. 105-107. 



