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IN 1877, under the name Cladosporium carpophilum Thum., the type-specimen of the species Fusicladium carpophilum (Thum.) Oudem. was described on peach fruits, grown in Austria. Since that time, the species has been recorded from most parts of the world on apricots, plums and almonds, as well as peaches.

The variation of eighty isolates of the pear scab fungus, Venturia pirina Aderh., collected from various parts of England and from different pear varieties has been studied in culture. No correlation has been found between the different types and the host varieties from which they originated. This lack of correlation is attributed to the fact that isolates differing widely in morphology and nutritional requirements can be obtained from individual hosts. Neither did the variation appear to be clearly related to geography as in Germany.

INFECTION of plants by certain virus and fungus pathogens results in an increase in polyphenol synthesis and oxidation1,2. This has been interpreted as a possible defence reaction by host tissue. Investigations of resistance of specific varieties of pear, Pyrus communis, to invasion by Venturia pirina indicated that polyphenol metabolism might be associated with resistance3. A project was initiated to determine whether the location and concentration of phenolic substances in pear might be of possible significance in influencing the channels of infection and relative susceptibility of specific pear tissues to fire blight caused by Erwinia amylovora. The relation of the arbutin-hydroquinone complex in pear blossoms to invasion by the fire blight organism is herein reported.

VENTURIA CLINTONII Peck, in good maturity, occurred on fallen leaves of Cornus rugosa (circinata) at Sturgeon Bay, Door Co., April 23. Coll. J. S. Boyle. The upper leaf surface has rounded, black, stromatoid patches, while most of the perithecia are hypophyllous and concentrated below the patches, but by no means closely confined to them. Cultures from ascopores were made, but no conidia were produced. So far as I am aware this has not yet been connected with a parasitic imperfect stage. Also collected at Cactus BEluff, Town of Prairie du Sac, Sauk Co., May 7.