FUNGI. 241 



body of a healthy insect, and there germinates. The 

 germinating tube enters the body, either by perfora- 

 tion, or by taking advantage of some natural opening, 

 and when it has entered the body it develops rapidly 

 at the expense of the tissues, producing hyphal 

 bodies, or short thick fragments 

 of variable form (Fig. 44), which 

 continue to increase by budding or 

 division until the body is filled with 

 them, and consequently the death ^^^ _^ . j^^j ^^^.^^ 

 of the insect supervenes. A mass 

 of hyphal bodies being produced within the insect, if 

 the conditions of temperature and moisture are 

 favourable, these commence to germinate. But, if the 

 conditions are not favourable, a resting condition 

 occurs, which may extend for several weeks, until 

 proper conditions present themselves for further de- 

 velopment. 



Having appropriated the w^hole of the nourishment 

 which the host affords, and there is a sufficiently 

 moist atmosphere and high temperature, the hyphal 

 bodies germinate with great rapidity; in simple cases 

 producing a thread, which grows directly into the 

 outer air, and develops one or more conidia ; in 

 other cases the fertile thread, or conidiophore, is in- 

 definitely branched (Fig. 45). The branching depends 

 very much upon favourable conditions. The threads, 

 which arise directly or indirectly from the hyphal 

 bodies, grow outwards rapidly, burst through the 

 integuments of the dead insect in spongy masses, which 

 are normally whitish, and produce the conidia in pro- 

 fusion. These conidia are terminal on the branches, 



R 



