200 Transactions British Mycological Society. 



the oak it would appear that only very young leaves are 

 susceptible, but it is possible that conidia produced by the 

 beech might give a higher percentage of successful infections. 

 It should perhaps be added that these observations were con- 

 firmed by microscopic examination, and that at the time 

 Neger's experiments were unknown to the writer. 



One of the most interesting features connected with the 

 above phenomenon is its comparative infrequency. The 

 occurrence of Oak Mildew on Beech was recorded ten years 

 ago by Griffon and Maublanc, yet the Beech remains as generally 

 immune from attack to-day as it did then. On the Oak the 

 mildew is found specially on closely cut hedges, coppiced plants, 

 and on the young summer growth on the lower parts of trees. 

 Although the Beech is not coppiced and makes little secondary 

 growth, closely trimmed Beech hedges are general throughout 

 the country but in no case have these been observed attacked 

 by the mildew. 



ENTOMOGENOUS FUNGI NEW TO 

 BRITAIN. 



By A.D. Cotton, F.L.S. 



Very few observations have been made in this country on 

 entomogenous fungi and the occurrence of any species not 

 hitherto recorded is worthy of a special note. Of the following 

 species the three on Aphides were discovered by Miss D. J. Jack- 

 son in the course of research carried on by her on the distribution 

 of these insects in Scotland. They were forwarded to the 

 Pathological Laboratory at Kew for determination and I am 

 indebted to her for permission to publish the records. The 

 fourth species Enipusa sphaerosperma was collected by Mr. W. 

 Watson and determined by Miss E. M. Wakefield. The three 

 species of Empusae appear to be new records for Britain, but 

 it is probable that they are not uncommon. 



Since the descriptions of these three fungi are not readily 

 accessible to all workers, the diagnoses as given in Thaxter's 

 excellent monograph " The Entomophthoreae of the United 

 States" are added to each. 



