208 INJURIOUS INSECTS AND FUNGI. [Dec. 1894. 



Fig. 2. 



Hypha aud Conldia of Macrosporiiun solani, 



and divided by transverse and longitudinal septa, while in the 

 Phytophthora infestans the conidia are colourless and egg-shaped. 



The hyphae and the conidia (spores) of Macrosporium solani are 

 illustrated in Figure 2. From the mycelial hyphse nt the base 

 of the figure the conidiophores are put forth bearing the conidia, 

 which fall out when ripe and may be distributed widely. 



The fungus Macrosporium solani helong^ to the family 

 Sphceriacece of the Ascomycetes. Its perfect life history is not 

 known. It is probably, like many species of Macrosporium, an 

 early or conidiophorous form of some known or unknown species 

 oiSphcBria. The conidia from this form may rest for the winter 

 on the decaying leaves and stems of potato plants or on the 

 ground. Mr. Weed states positively that it winters over in the 

 dead leaves and stems of the potato plants. 



In the reports before alluded to, Mr. Galloway gives the 

 results of spraying with Bordeaux mixture potato plants infected 

 with this parasite. He says :— " For blight and the Macro- 

 sporium disease nothing so effective as the Bordeaux mixture 

 has be?n found." These experiments were made in two separate 

 fields with exceedingly gratifying results. 



The Bordeaux mixture used was composed of about 14 lbs. of 

 sulphate of copper and 8 lbs. of lime to 1 00 gallons of water. 



Mr. Fletcher, in describing experiments with Bordeaux mixture 

 in Canada for the Macrosporium disease, also testifies to its 

 efficacy. 



In potato fi.elds in Kent, where large experiments were made 

 with the Bordeaux mixture for the ordinary potato disease, it was 

 noticed that there was but little injury from the Macrosporivym 

 Q>nd. the Phytaphthom the- spray eti rows,' but upon the 



