226 



RESEARCHES ON FUNGI 



(5) As in (4), the pairs of conjugated primary conidia do not 

 remain seated on the promycelium but, shortly after conjugation 



Fig. 111. — Tilletia tritici. A semi-diagrammatic representation of a pair of con- 

 jugated primary conidia (the authors' primary sterigmata) which was shaken 

 off the promycelium (basidium-body) and fell on to a nutrient substratum of 

 malt-agar and there produced a mycelium which gave rise to secondary conidia 

 (the authors' secondary basidiospores). A, the primary conidia just after 

 falling ; B, a few hours later, one of them has sent out a lateral hypha, the 

 protoplasm is creeping out of the ends of the primary conidia and two septa 

 have already been formed ; C, still later, the lateral hypha has become branched, 

 the migration of the protoplasm from the primary conidia into the mycelium 

 and the formation of septa in the primary conidia are further advanced ; 

 D, some days later, the primary conidia p, which have now lost all their proto- 

 plasm, have given rise to an extensive mycelium m characterised by the winding 

 course of its hyphae and by the formation and discharge of secondary conidia 

 (the authors' secondary basidiospores) developed on short sterigmata : a, a very 

 rudimentary secondary conidium symmetrically placed on the end of its 

 sterigma ; b, a half-grown secondary conidium asymmetrically situated on the 

 end of its sterigma ; c and d, two full-grown secondary conidia, protoplasm is 

 still flowing into c but no longer into d ; e, a secondary conidium which if 

 excreting a drop of liquid from its hilum and is about to be discharged ; /, a 

 secondary conidium and its drop which have just been discharged from the 

 sterigma g ; h, a sterigma from which a secondary conidium has been dis- 

 charged ; the mycelium exhibits septa in its empty parts from which the 

 protoplasm has migrated away into terminal hyphae and secondary conidia. 

 Magnification, 660. 



has taken place, become detached from the promycelium and settle 

 on the substratum. Here, as shown in Fig. Ill, each H -shaped 



