GRAMINEOUS CROPS. 



97 



was first described by the late Rev. M. J. Berkeley, 

 F.R.S., in the Journal Linnean Society (vol. xiii. p. 176). 

 This fungus occurs chiefly in the South and South-west 

 of England, and appears only to attack certain grasses 

 growing on calcareous and siliceous soUs. The reason for 



-A 



Fig. 38. — ISAEIA PUCIFOKMIS OF GeASSES 



A. A grass infested with the fungus (a). 



B. End of a fongus tuft (a) with conidia (spores). 



C. Conidia. x 670 diam. (Zeiss' E., 4oc.) 



the growth of I.fuciformis on certain grasses growing 

 on the previously mentioned soils, may be due to the fact 

 that both calcareous and siliceous soils contain (as a rule) 

 smaller percentages of iron oxide than argillaceous soils. 



