614 SECTIONAL TRANSACTIONS.— K. 



fir which, as far as is known, occurs only in Europe. The differentiation of this 

 parasitic species of Phomopsis from species and forms closely related became a highly 

 important phytopathological problem. 



In general, efforts made to induce the Phomopsis forms to produce the perfect 

 stage were unsuccessful. Forms of Diaporthe pitya Sacc. on Douglas fir and Sitka 

 spruces were isolated from single ascospores and single asci. These produced in 

 culture either the perfect or imperfect stage, the latter being identical morphologically 

 with forms of a Phomopsis species collected on Taxus, Taxodium, Sequoia, Pinvs, 

 Picea, Abies, Tsuga, Larix, Pseudotsuga, Thujopsis, Thuja, Cupressus and Juniperus. 

 Culturally the forms of this species having so wide a host distribution showed close 

 agreement. These forms are all regarded as Phomopsis occulta Trav. 



The original type specimen of Diaporthe conorum (Desm.) Niessl. has been 

 examined. This fungus appears to be identical with the type of D. occulta, and with 

 D. pitya, both of which may be regarded as synonyms. There are indications of 

 relationships between these conifer forms and similar forms on broad-leaved hosts. 



It has been found as a result of the cultural study of Phomopsis and Diaporthe 

 forms that spore size and shape are quite constant within a given specific range, 

 irrespective of the host substratum. Stroma characters can be affected by host 

 and growth influences. 



Miss W. M. Page. — Sfore Discharge in Sordaria and its Allies. 



Spore discharge in several species of the lower Pyrenomycetes has been studied. 



In species of Chcetomium the spores are liberated from the asci within the body 

 of the perithecium and, oozing through the neck, become entangled in the hairs. 

 SUght movements of the hairs due to changes in humidity assist in the dispersal of 

 the spores. 



Species of Sordaria, Podospora and Philocopra discharge their spores with con- 

 siderable energy. In this process the movements of the paraphyses and periphyses 

 take part ; the force of ejection and the duration of discharge vary in different species. 

 In several specfes perithecia with more than one neck have been observed. 



Prof. Dame Helen Gwynne-Vaughan and Mrs. H. S. Williamson.— 



Heterothallism in Humaria granulata. 



Humaria granulata Quel, is a small orange, coprophilous, discomycetous fungus. 

 Blackman and Fraser described its development in 1906 and reported a single 

 oogonium in each young fruit and no antheridium. The species has now been grown 

 on agar and these observations have been confirmed and extended. Humaria fruits 

 readily in mass culture ; the spores germmate under natural conditions some eight 

 months after they are shed ; their development after five months can be induced by 

 artificial means. In single spore culture all mycelia produce archicarps, but these 

 die and no fruits are developed. Fruiting occurs along the line of junction of suitable 

 mycelia which have proved to be of two kinds ( + ) and ( — ). Since both bear female 

 organs the distinction between them is not regarded as sexual. 



Afternoon. 

 Excursion to Glasgow Parks. 



Department of Forestry. 

 Mr. Alex. L. Howard. — Timber Supplies from within the British Empire. 



Present practices. The comparative merits of various timbers in commercial 

 use. Information as to new woods. Illustrated by forestry and other views. 



Mr. M. Y. Orr.— TAe Relative Value of Anatomical Characters in the 

 Identification of Conifers, with special reference to Chinese Species in 

 Cultivation. 



Prof. J. H. Priestley. — The Living Tree : its Increase in Girth. 



Prof. P. Groom. — The Antiseptic Preservation of Timber. 



