270 



that we know very little about the subject. A curious statement is made by 

 Delile (Dclilc Exam, de la Phospho. dc VAg. dc VOliv. p. 8,^ to the effect that Agar- 

 ieus olearius did not give out its light during the day-time when placed in dark- 

 ness. Tulasne regretted that he himself omitted to test the fact with the 

 specimens he had imder hand ; but with regard to Rhizomorpha he asserts, that 

 specimens he had seen luminous at night, when placed in the dark at mid-day 

 gave no signs of luminosity. 



There are many other undetermined problems connected with the subject, 

 but those I have glanced at may be sufficient to show that a large field of enquiry 

 lies before the student who will have the courage and perseverance to undertake 

 the task ; and if any amongst us is induced to do so, the object of this short paper 

 will be answered. 



THE NEW SCLEROTIUM DISEASE IN IRISH POTATOES. 



This subject was introduced to the notice of the members by Dr. Bull. 



It is to be regretted that no notes remain upon record, but this matter has 

 been exhaustively treated, and fully illustrated by Mr. Worthington G. Smith in 

 his Diseases of Field and Oarden Crops. (See chap iv., page 17, et seg., of his 

 small book, first edition.) This popular treatise and excellent guide, dedicated to 

 "Dr. Bull, of Hereford, and the Officers and Members of the Woolhope Club," 

 should be studied by e\'ery educated horticulturist and agriculturist, as well as by 

 every member of the Woolhope Naturalists' Field Club. 



A MONOGRAPH OF THE BRITISH HYPOMYCES. 



[By Chas. B. Ploweight.] 



(With illustrations of all species, by Dr. M. C. Cooke, M.A., A.L.S.) 



There are several points which render the members of this genus specially 

 interesting to the mycologist, and which make it a promising field for the worker. 

 In the first place, the nature of the matrices upon which the species grow fungi. 

 Hiipomyces are inter alia fungi, growing upon other fungi. These fungous hosts 

 vary in nature and in quality very considerably. Some are living fungi, which 

 afford the Hypomyces a home long ere they themselves have attained maturity ; 

 for example, H. liiteo-virens, Fr., grows upon agarics. It has occurred near 

 King's Lynn for three successive seasons, yet, although attention has been 

 especially directed to this point, it has not, as yet, been possible to determine with 

 certainty what the agaric is, for the simple reason that the Hypomyces attacks it 

 before it appears above ground, and so alters its appearance, that beyond recog- 

 nising the fact that it is an agaric, its genus, much less its species, cannot be 



