44 BOTANICAL GAZETTE [JULY 
On a recent trip (June 1920) through Texas many areas were 
revisited which in May and November of 1916 showed an abun- 
dance of Ravenelia infection of many different species, yet only occa- 
sionally was any Ravenelia found, although a careful search was 
made on hundreds of plants which in 1916 were literally covered 
with Ravenelia sori. The species of Ravenelia so abundant in 1916 
were as follows: R. siderocarpi, R. papillifera, R. roemerianae, 
R. mesillana, R. gracilis, R. leucaenae, R. siliquae, and Neoravenelia 
holwayi; of these only R. siliquae was at all common in 1920. 
This would indicate that certain years are very favorable for ‘the 
propagation and dissemination of species of Ravenelia. This 
fact, of course, is well known in connection with various species of 
grain rusts. 
OFFICE OF INVESTIGATIONS FoREST PATHOLOGY 
UREAU OF PLANT INDUSTRY 
ALBUQUERQUE, N.M 
