306 Journal of Agricultural Research voi.xx,No.4 



found in the alfalfa parasite corresponding, for example, to Plate 48, 

 A-D, ra, rb; although, to be sure, the attachment of the "Sammelzellen" 

 to the convex haustoria-bearing side would be at variance with any close 

 homology. It appears not unreasonable, however, to suspect that Biis- 

 gen was in error in regard to this point and that the resting spore may 

 be attached by its concave side, the concavity, as in Urophlyctis spp. 

 generally, very probably being opposite the side bearing the haustoria. 

 Clinton (5) noted the presence of a rhizoid-like process on the side of 

 the "Sammelzellen" toward the young sporangium in Physoderma 

 (Cladochytrium) macular e and figured it both as a terminal apical struc- 

 ture before the development of the resting sporangium has been initiated 

 and as a median whorl after the latter has been formed. Regarding its 

 function he states that — 



The exact nature of these processes is not clearly shown, though they seem to bind 

 the sporangium cell to the Sammelzellen. 



In his figure 32 he shows a similar process attached to an element that 

 appears to be a young resting spore, although he makes no reference to 

 this condition in the text. 



Schroeter (28) observed the apical apparatus on the vegetative cells of 

 Urophlyctis pulposa, designating it as — 



ein Kronchen, ein Schopf feiner und kurzer, oft verzweigter Protoplasma Anhangsel. 



Vuillemin (35), who later studied the same species as well as the beet 

 parasite, appears to have recognized the apparatus as consisting of a 

 "tronc" bearing terminally a "houppe" of short ramifying processes — 

 the "panache terminate. " To these processes and to the haustoria on 

 the resting spores, as well as to the "appareil nourricier" generally, he 

 (36) assigned a structure identical to that of the striated muscle fiber of 

 animals. We have not been able to distinguish anything suggesting 

 striation in any portion of the thallus of U. alfalfae. The haus- 

 toria here, moreover, appear to have a membrane that seems to persist 

 after the contents have been withdrawn by plasmolysis or have degenerat- 

 ed. The history of the development of the haustoria on the resting 

 spore as given for the beet parasite again is at variance with their develop- 

 ment as observed in U. alfalfae. For the resting spore, according to 

 Vuillemin, ccmes about by the swelling of the "sommet du tronc du pan- 

 ache" in such a way that — 



Les branches se trouvent dissociees en plusiers buissons et entrainc'es a diverses 

 hauteurs sur la boule terminale, tandis que d'autres fragments sont restes a la base. 



Whereas in U. alfalfae the resting spore is initiated as a bud from the tip 

 of the axial haustorial element, never involving translocation of any 

 haustorial ramification. And as has been pointed out, the haustoria on 

 the resting spores are subsequently developed as new structures in a well- 

 defined zone and are not portions of the apical haustorium distributed 



