THOMAS: INFECTION OF APIUM GRAVEOLENS vf 
On the seed the fungus does not produce a definite spot. 
The pycnidium is found imbedded in the pericarp with only a 
small spreading of the mycelium into adjacent tissue. In the 
sections studied, the mycelium did not penetrate to the embryo. 
That this may occur, however, seems reasonably to be expected 
and it would probably result in most cases in inhibiting germina- 
tion of the seed. _ 
CULTURAL CHARACTERS OF THE FUNGUS 
The fungus grows readily although slowly on a variety of 
media in pure culture. On starch,* beef peptone, and celery 
decoction agars the fungus produced somewhat greater radial 
growth at comparatively low temperatures (13°—19° C.) than at a 
temperature ranging from 22° to 27° C. On starch agar, which 
was the most satisfactory medium tested, a colony 15-18 mm. in 
diameter was produced in four weeks with mature pycnidia and 
considerable superficial fine white mycelium. As the culture 
ages the mycelium becomes coarser and darker until finally the 
surface of the medium is covered with a dense black weft. On 
the agar prepared from a decoction of celery leaves, the growth 
is similar to that described above but less vigorous. In marked 
contrast is the colony produced on ordinary beef peptone agar. 
The mycelium is dark and coarse from the beginning, radial 
growth is small and the result is an irregularly pulvinate colony 
very densely compacted. A-somewhat similar growth was ob- 
tained on steamed coconut, bean stems, and petioles of celery 
and beet. When celery leaves were mixed with garden soil and 
steamed, no growth of the fungus could be obtained. Clean 
white sand was substituted for the soil and a good vigorous growth 
followed even’spreading into the sand adjacent to the celery tissue. 
SPECIALIZATION OF SEPTORIA APII AS TO HOSTS 
It has been accepted by a number of pathologists in Europe, 
America and elsewhere that the Septoria of celery is transferable 
to parsley and vice versa, although I have found no record of 
inoculations to settle this question definitely. I have attempted 
to determne to what extent the celery fungus has become special- 
bi Czapek’s formula, with 10 gm. corn starch substituted for the sugar. 
