ZOOLOGY AND BOTANY, MICROSCOPY, ETC. '.Dfi 



'different genera. Pohjporus vohatus Peck is made the type of a new- 

 genus Cryptoporus. In this plant a " thick volva-like extension of the 

 margin of the pileus covers the pores, with the exception of a small 

 ■circular aperture." The author records a new genus of Hyphomycetes, 

 Plectrothriz, near to Monosporium. The spores are borne on spinose 

 branches near the tops of the fertile hyphse. They grew on leaves of 

 Vaccinium macrocarpon which were kept in a moist chamber, and which 

 had previously developed Pestalozzia Gupini. 



Vegetable Pathology.* — F. P. Brzezinski publishes the result of his 

 research on fruit-trees injured by canker and gummosis. The canker of 

 apple-trees has been hitherto ascribed to the action of a fungus, Nectria 

 ditissima. The writer has conducted a long series of experiments, and 

 has come to the conclusion that the nectria is merely saprophytic on the 

 damaged tissue, and that the canker is primarily due to the action of 

 bacteria. He invariably found microbes in the diseased parts, and with 

 these he inoculated healthy trees and reproduced the canker. Brzezinski 

 considers canker to be a contagious malady, and one which may be latent 

 for years in a seemingly healthy tree. So long as the surroundings are 

 ■conducive to healthy growth the tree shows no sign of canker, but if 

 unfavourable conditions occur, or if the tree is old, the disease at once 

 becomes manifest. The canker bacterium has the form of short rods 

 divided in two twin globules. It is easily cultivated on nutritive media. 

 High temperatures are fatal to it, but it thrives and multiplies in the 

 cold down to 0° C. 



The bacterium of Pear canker cannot be distinguished from that 

 of the Apple, though in artificial cultures there is a slight difference. 

 Gummosis of the Peach, Apricot, Plum, and Cherry has much analogy 

 with canker ; it also is due to the action of bacteria. The writer is of 

 opinion that the Cherry bacterium differs from that of the other fruit- 

 trees ; it is similar in form, but quite distinct in artificial cultures. 

 Oummosis commences with discoloured streaks in the tissue penetrating 

 the wood of the branches, which soon thereafter begin to secrete gum 

 from open wounds. The young twigs and the fruits are also liable to 

 the disease. 



Fungi on Andromeda polifolia.f — P. Hennings has described a new 

 species, Godronia Andromedse, which he found growing on Andromeda. 

 It is closely related to G. urceoliformis and G. Ledi, which grow on 

 Vaccinium Myrtillus. He also found, growing along with Godronia, a 

 new species of the Melanconiae, Seplomyxa Andromedse. He is of 

 opinion that the latter is the pycnidial form of Godronia. Several 

 i ither pycnidial forms have been observed in association with species of 

 Godronia. Schroter found Sphserocista schizothecioides Preuss. growing 

 with Godronia Ericse. Dothichiza Viburni Karst. and Sphseronema Viburni 

 Fusk. are associated with Godronia Viburni, and Brefeld noted in his 

 cultures a series of conidial forms pertaining to G. urceolus. Hennings 

 found also on Andromeda specimens of Mollisia cinerea var. nov. Andro- 

 medse and of Lachnum virgineum. 



* Comptes Bendus, cxxxiv. (1902) pp. 1170-3. 



t Verb. Bot. Prov. Brandenb., xliii. (1902) pp. 102-4. See also CentralbL Bakt. 

 2 te Abt, viii. (1902) p. 813. 



