4 I^RIERLEY, Life-History of LeptospliiEvia Lcvianecc. 



somewhat straight course for some distance. {PL \.,Fig. i.) 

 The individual cells are regular, colourless and uninucleate. 

 Frequently the contents appear finely granular, and occa- 

 sionally minute, highly refractive substances are present. 

 Arising as branches from this lumen mjxelium, and as 

 secondary hyphffi from the pcrithecia, is a weft of threads 

 which spreads very extensively in an intercellular manner, 

 jM-incipally through the middle and medu-llary la}-ers of 

 the host tissue. It is from this portion of the mycelium 

 that the fruiting bodies take origin. Branches from the 

 intercellular hyphffi and occasionalh' directly from the 

 hyi)haf of the lumen enter the host cells. The protoplasm 

 o{ Leviaiiea cells is spread in a thin peripheral ]a}-er about 

 a large central vacuole and the fungal haustoria usually 

 directly enter the latter, within which they freely branch. 

 (P/. /., Fig. 2.) Not infrequently the haustoria appear to 

 enter the protoplasm. {PI. /., Fig. 3.) 



Lemauca cq\\< arc connected b\' minute pits, the proto- 

 plasmic connection being severed by the middle lamella. 

 These pits afford points of entr}- to the haustoria, but the 

 latter also directly penetrate the cell walls in the absence 

 of pits. 



The mycelium of LeptospJu^ria Leina7icce exhibits 

 hyphal dilations, terminally or in an intercalary position. 

 Not infrequently a dumbbell-shaped structure is formed 

 by dilation of a hypha immediatel}' external and internal 

 to a cell wall. {PL /., Fig. 4.) These hyphal swellings 

 may or may not be cut off by septa, and usually contain 

 s-omevvhat denser and more refractive contents. 



In many cases, as Woronin noted, a vacuole ma)' be 

 present. 



Reproduction. 



Woronin ■ remarks that "in addition to the perithecia 

 no other reproductive organs have been found in Sphceria 



