ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 215 



numerous antheridial cells, iu rows which extend obliquely inward and 

 upward, emptying into a common cavity. 



Euhaplomyces g. n. Receptacle consisting of two cells, the upper 

 being a free stalked antherid and a stalked perithece. Antherid conical, 

 consisting of a single stalk-cell, followed by a basal cell, from which 

 is separated a group of smaller cells, some of which extend upward 

 and inward to form antheridial cells; above these follow three external 

 marginal cells, the lowest of which lies beside the antheridial cells ; 

 the uppermost succeeded by a conical chamber terminating in a pore, 

 and extending downwards along the inner sides of the marginal cells 

 to form a cavity into which the antheridial cells empty. Perithece re- 

 sembling that of Haplomyces, and having two ascogenous cells. 



Dioicomyces g. n. Male individual consisting of four superposed 

 cells, the upper of which is a simple antherid bearing a sub-terminal 

 discharge-tube. Receptacle of the female individual ending distally 

 in a peculiarly modified sterile cell corresponding to the upper spore- 

 segment ; the sub-basal cell producing a single perithece laterally, and 

 separated from the sterile terminal cell by a second small cell. Peri- 

 thece tree-stalked, the ascogenous cell single ; the spores more or less 

 obliquely once-septate, and of two kinds corresponding to the sexes. 



Acompsomyces g. n. Receptacle 2-celled, bearing an antheridial 

 branch terminally and a single perithece laterally. Antherid consist- 

 ing of several superposed cells, from which single simple antherids are 

 borne directly. Perithece borne on a stalk, the cavity of which becomes 

 continuous with that of the ascogenous cavity. 



Slichomyces g. n. Receptacle consisting of two cells, the upper 

 beariug one or more stalked peritheces laterally, and an antheridial 

 appendage terminally. The appendage consisting of several superposed 

 cells, the lowest sterile, or having one or two opposite lateral peritheces, 

 those above it bearing opposite lateral branchlets distally, the series 

 ending in a terminal sterile branch. Antherids simple, flask-shaped, 

 free, borne in small groups on short branchlets. 



Kainomyces g. n. Receptacle as in Zodiomyces, broad and flattened, 

 consisting of a single basal cell and a typical foot, above which the 

 successive cells become variously divided by longitudinal septa into 

 transverse rows or tiers of cells ; the distal portion more or less definitely 

 distinguished, and consisting of superposed cells, the lowest of which 

 alone becomes longitudinally divided, all producing laterally anthe- 

 ridial (?) branches ; several of the tiers immediately below this appen- 

 diculate portion growing out laterally at right angles to the main axis 

 of the receptacle on one or both sides to form " perithecial branches " 

 consisting of superposed cells, and terminated by solitary peritheces. 

 The perithece of peculiar form, with six wall-cells in each row in addi- 

 tion to the lip-cells ; the base of the trichogyne persistent in the form 

 of a peculiarly modified unicellular appendage. 



Contributions to the Biology of the Erysiphaceae. *— In this paper 

 F. W. Neger makes a second communication on the Erysiphaceae. It 

 is largely devoted to a study of the form genus Oidium, the conidial 

 form of the fungus. The author has germinated conidia gathered 

 from a great variety of host-plants, and takes special note of the posi- 



* Flora, xc. (1902) pp. 221-72. 



