238 DISEASES OF FIELD & GARDEN CROPS. [OH. xxvm. 



Dr. M. C. Cooke, M.A., in Grevellia, vol. xii., March 

 1884, p. 77, has, since the above notes were written, 

 described Barya aurantiaca, P. and Wils., as a species 

 under the name of Claviceps Wilsoni, Cke. He says it 

 differs from all other species of Claviceps in the elongated 

 clavate capitulum and in the lax manner in which the 

 conceptacles or perithecia are immersed. "We do not, 

 however, esteem this form to be worthy of specific rank. 



We consider also that the Claviceps microcephala, Tul., 

 on reeds is not a species but a mere variety of C. pur- 

 purea, Tul. One is connected with the other by a con- 

 tinuous series of intermediate forms, and the typical form 

 of C. purpurea, Tul., sometimes occurs on the ergots of 

 reeds. If these two fungi should ultimately prove to be 

 distinct, hybrids undoubtedly occur, which probably 

 arise from the spores belonging to the two different forms 

 of Claviceps lighting on a single grass flower, and there 

 bursting and producing a hybrid Sphacelia, which is the 

 beginning of ergot. Or if the spores of the Oidiuni state 

 of Claviceps purpurea, Tul., and C. microcephala, Tul., 

 were blown on to the same grass flower, the watery con- 

 tents of the burst spores or conidia would conjoin and 

 form a hybrid Sphacelia. 



