Shear and Dodge : Patellina, Leptothyrium, Peziza 189 



that the germ tubes are able to penetrate the uninjured, normal 

 cuticle of the strawberry. 



As the skin of many berries is usually injured and insects prob- 

 ably carry spores from berry to berry, it is frequently only neces- 

 sary to provide moisture to insure development of sporodochia. 

 It was found to be much more satisfactory to carry on this work 

 with blackberries and dewberries as individual carpels could be 

 carefully inspected before inoculation. The same experiments 

 were carried out on these berries with strains of the fungus found 

 on the berries in 'nature. The fungus spreads to carpels adjoin- 

 ing the one inoculated but slowly. Over-ripening brings about a 

 softening or breaking of the cuticle so that such carpels become 

 infected following surface inoculation. Berries in boxes were 

 sprayed with a suspension of conidia, shipped from North Caro- 

 lina to New York City and then placed in damp chambers. They 

 developed large numbers of sporodochia. Boxes of berries simi- 

 larly treated except that hulls were left on in picking, arrived in 

 excellent condition and very few sporodochia could be found 

 even after the berries had been left several days in damp cham- 

 bers. The injury to the fruit caused by pulling off the hull ap- 

 parently provides opportunity for the entrance of the fungus as 

 berries picked with the hulls on are certainly not so susceptible 

 to this and other fruit rot fungi which are not able to penetrate 

 the unbroken cuticular layer. 



It is also a question whether this fungus is able to penetrate the 

 cuticle and epidermis of a normal living leaf. It is likely in most 

 cases where sporodochia are found on living leaves that some 

 injury has occurred to the epidermis. There is frequently evi- 

 dence of insect injury in such cases. Under favorable condi- 

 tions the fungus having gained entrance to the tissue appears to 

 be able to spread to the adjoining tissue so that the spots become 

 larger and quite characteristic as noted by Halsted (1893) on 

 Rhus and Massalongo (1908) on leaves of Rubus, also by Stevens 

 and Peterson (1916) on fruit of strawberry. The pycnidial 

 stage is seldom found on living leaves but Massalongo noted 

 that it sometimes occurs on spots on Rubus leaves. Both stages 

 occurred very abundantly here during August and September, 



