574 THE FUNGI WHICH CAUSE PLANT DISEASE 



elliptical, hyaline or variously colored. For the ascigerous stage 

 see page 167. 



The conidial stages of many Penicilliums have been given 

 searching investigation and comparative study by Thom."^ 

 P. glaucum Lk. 



Hj-phffi effused, creeping, septate, interwoven, white, conidio- 

 phores penicillate, branches single or in pairs, erect, forked; conidia 

 globose to broadly elliptic, smooth, hyaline, 

 with a tinge of green, 4 /x. 



It is the cause of rot of ripe oranges, lemons, 

 apples, etc. 

 P. italicum Weh. is described as a wound 



22 T * 



parasite on oranges by Massee. It is very 

 similar in appearance to P. glaucirai but a 

 Fig. 385.— PenicUlium. little greener; conidia elliptic-oblong, 7-9 x 4 ai. 

 After Brefeld. p_ jigitatum (Fr.) Sacc. 



Similar to the preceding species in habit but the conidia are 

 white in mass, 4-6 ii. Often associated with, and similar in effects 

 to P. glaucum. 



P. olivaceum Weh. is found on citrous fruits; 



P. luteum Zuk. on apple. 



An undetermined species is reported as the cause of a white dry 

 rot of sweet potatoes.''" 



Various other species of the genus occur on fruits and vegetables 

 causing their decay. 



Gliocladium Corda (p. 572) 



Hyphse effused, spreading; conidiophores and conidia as in 

 Penicillium but the conidia surrounded by a mass of mucus. 



A genus of only about ten species. 



G agaricinum C. &. M. arrests growth and breaks the pilei of 

 mushrooms. 



Botrytideae (p. 566) 



Conidiophores elongate, simple or branched but not inflated, 

 and the branches not verticillate; conidia borne variously, globose 

 or ovate to elliptic. 



