178 



Mycologia 



Pycnia were evident on June 13 in great abundance and aecia fol- 

 lowed in two or three weeks. Two host plants were used and 

 the infection was marked on both. The aecia were without 

 doubt Peridermium decolorans Peck. Another sowing on June 

 17 gave pycnia on June 27 followed by aecia. This confirms the 

 work of last year. (Mycol. 3 : 70. 191 1.) 



Melampsoropsis Cassandrae (Peck & Clinton) Arthur 



Teliosporic material of this rust on Chamaedaphne calyculata 

 (L.) Moench was sown on Picea rubra (DuRoi) Dietr. on June 

 16; pycnia were noticed on June 26, and aecia were mature by 

 July 16. Both pycnia and aecia were very abundant. Another 

 sowing on Picca luariana (Mill.) BSP. on June 17 gave pycnia 

 which were noticed first on July 3. Aecia followed, but not in 

 abundance, probably owing to the maturity of the leaves. The 

 aecia belonged to Peridermium consimile Arthur and Kern. Fre- 

 quent collections of aecia were made in the field on the Picea that 

 grew beside the Ledum, which bore germinating telia in the 

 spring. (For previous culture see Mycol. 3: 68. 1911.) 



]\Ielampsoropsis abietina (A. & S.) Arthur 



Teliosporic material on Ledum groenlandicum was sown on 

 Picea rubra on July 16, with pycnia on June 27 and aecia on July 

 8, both in great abundance. A sowing was tried on Picea cana- 

 densis without result, but the leaves were too old for the 

 experiment to have any value as negative evidence. This con- 

 firms the work of last year (Mycol. 3: 69. 191 1). The aecia 

 were found to be Peridermium abietinum. Several collections 

 were made in the field beside where the telia were germinating 

 ■on Ledum in the spring. 



Uromyces Scirpi Burr. 



Teliosporic material of this rust on Scirpus campestris var. 

 paludosus (A. Nelson) Fernald {S. paludosus A. Nelson) was 

 sown on Cicuta maculata L. on June 9. Pycnia appeared on 

 June 16 and aecia followed in a short time, both in abundance. 

 Arthur {Jour. Myc. 13: 199. 1907; 14: 17. 1908; Mycol. i: 



