204 BOTANICAL GAZETTE [MARCH 
embodied in an account of the origin of the ascocarp in this species 
(FITZPATRICK 27). During the course of this investigation the 
examination of certain slides disclosed the fact that the material 
was favorable for a study of the sexual process. Additional slides 
were then prepared, and material of all ages was given critical 
examination, 
The apothecia were fixed in the field in medium strength 
chromo-acetic acid fixer, and were later imbedded in paraffin. The 
material was studied in serial sections 4-7 » in thickness and was 
stained in most cases with Haidenhain’s iron alum-haematoxylin, 
although for certain stages the shortened sutiponds s triple stain 
proved more satisfactory. 
Certain of the apothecia on which the investigation is based were 
sectioned and stained in the laboratories of the Brooklyn Botanic 
Garden in the summer of 1915, while the writer held a visiting 
fellowship at that institution. He wishes to express here his 
appreciation of the courtesy of Director C. S. GAGER in extending 
to him all the facilities of the laboratories and gardens, and to 
acknowledge his indebtedness to Dr. E. W. Ottve for many kind- 
nesses, including helpful suggestions concerning microtechnique. 
Subsequently other apothecia were sectioned and stained in the 
laboratories of the Department of Plant Pathology at Cornell 
University. All the critical study of the material was made at the 
latter institution during the spring of 1916. The writer’s identifica- 
tion of the species as Rhizina undulata was confirmed independently 
by Dr. E. J. DurAnp and Dr. F. J. SEAvER. The completed manu- 
script was examined by Professor GEorGE F. ATKINSON. His 
criticisms, especially with reference to the interpretation of the 
meaning of the paired condition of the nuclei in the cells of the archi- 
carp, have been embodied in the text, and have resulted in extensive 
alterations. The writer wishes to express his appreciation of these 
avors. 
Vegetative hyphae 
The mycelium of Rhizina undulata is parasitic on the roots of 
various trees (HARTIG 42, 43, 44, TUBEUF 63, WEIR 64). It develops 
profusely in the soil also, enveloping the soil particles and smaller 
roots as a whitish, moldlike growth. On the surface of the ground 
