— 134 — 



the ends of erect hyphae arising from mycelium within the leaf 

 and surrounded by the ruptured epidermis. 



Fig. 5 — A ttredo sorus, the epidermis Fig. 6 — Uredo spores (X 



raised, broken and showing the spores. about 450 diameters. ) 



III. The Telentosporic Form. — This 

 consists of dark-brown spores 



(15-20x20-28 /x) 

 borne in the same manner as the uredo 

 spores and intermingled with them or 

 forming sori by themselves. (See Fig. 

 7. ) They undoubtedly arise from 

 Fig. 7— Teleutospores ( x branches of the mycelium producing the 

 about 450 diameters.) uredo spores 



OBSERVATIONS ON THE DEVELOPMENT OF THE CLOVER RUST. 



In October, '89, the Red Clover in the field was found to be af- 

 fected with the uredo and teleutosporic forms, and the White Clover 

 with all three forms. By December the uredo and teleutospores dis- 

 appeared from the living plants and were found only upon the 

 dead stems of the Red Clover. At various times during the winter, 

 — which was a very open one, — White Clover plants were found 

 whose petioles were affected with mycelium and spermagonia, but 

 no aecidia. A Red Clover was also found with swollen areas 

 upon its leaves. The plant being transferred to the conservatory, 

 these developed aecidia. These discoveries seem to indicate a 

 tendency at least, on the part of the aecidium stage to exist 

 through the winter in the form of mycelium and spermagonia. 



In November, Red and White Clover affected with the different 

 spore forms were placed in the conservator}*. The uredo and 

 teleutospores soon disappeared from the red clovers and a crop of 

 aecidia was developed. These in time, gave place on the same 

 plants to uredo and teleutospores again, which, arising from sori 



