G8 



Mycologia 



laboratory of Pictou Academy, no culture room being available. 

 It is hoped that the experiments may be repeated and extended 

 next spring. 



The writer wishes to acknowledge with deepest gratitude inval- 

 uable suggestions and assistance rendered by Dr. J. C. Arthur, 

 without which the cultures would probably not have been under- 

 taken. The writer's thanks are also due to Mr. John Macoun, 

 of the Geological Survey of Canada, for determining some of the 

 host plants. 



Melampsoropsis Cassandrae (Peck & Clinton) Arthur 

 The uredinial stage of this rust was collected on Chamae daphne 

 calyculata (L.) Moench in a large swamp during the summer of 

 1909. The host plants were kept under observation during the 

 next spring for the purpose of collecting the telial stage. It was 

 found in June in several places in the swamp and always on plants 

 growing beside Picea. The teliospores were first noticed germi- 

 nating on June 13 and they continued to germinate for some time 

 in moist weather. Leaves bearing mature telia were collected and 

 sowings were made on young trees of Picea rubra (DuRoi) Dietr. 

 on June 17. Pycnia appeared on June 29, followed by aecia in 

 a short time. Four plants were used and each sowing was suc- 

 cessful. The infection was marked, and was most abundant 

 just below where the telia-bearing leaves had been suspended. 

 Two trees obtained in the same place as those used in the experi- 

 ment were kept as controls and they remained free from aecia. 

 The aecia were found on examination to be Peridermium con- 

 simile Arth. & Kern. 



The spruces in the swamp near which the telia were found 

 were watched for the appearance of aecia. Both pycnia and aecia 

 developed abundantly and in such a position as to leave little 

 doubt that the infection came from the telia on Chamae 'daphne : 

 Collections were made on July 17 and 24. On the latter date the 

 aecia were mature. Part of the collection of July 17 was sent 

 to Dr. Arthur for determination. He replied that it was Peri- 

 dermium consimile Arth. & Kern and the host Picea rubra 

 (DuRoi) Dietr. 



Clinton (Rep. Conn. Agric. Exper. Sta. 6: 386. 1908) sowed 



