132 MICROSCOPIC PTJNGI. 



irregularlyj aud its contents (enclosed in a trans- 

 parent inner membrane) issuing from the orifice. 

 As in the case of the conidia, this body at first 

 contains vacuoles^ and is afterwards divided into 

 polyhedric portions ; these pass into zoospores, 

 which congregate at the centre into a globular 

 mass (plate X. fig. 207). They afterwards separate, 

 and for some minutes float about in the vesicle in. 

 which they were generated. Ultimately the mem- 

 brane ruptures, and the zoospores swim about in 

 water just as those produced from the conidia had 

 done. The number contained in each oospore is 

 considerable, and may be estimated at not less than 

 one hundred. 



The zoospores, whether produced from conidia 

 or from oospores, appear to be the same. The 

 movements of both in the water last from two to 

 three hours ; then they cease, the cilise disappear, 

 and the zoospores remain at rest, taking meanwhile 

 a globular form. Afterwards these spores (for 

 having ceased all motion they are no longer zoo- 

 spores) emit a thin tube from some portion of their 

 surface, such tube attaining a length of from two 

 to ten times that of the spore whence it pro- 

 ceeds. The extremity of these tubes swells and 

 forms a kind of cell, into which the contents of 

 the spore pass through the medium of the tube 

 (plate X. fig. 209). 



Thus far, and thus far only, has Dr. de Bary 

 been enabled to trace the development of the 



