CONTRIBUTIONS TO THE HISTORY OF THE DEVELOPMENT OF 
THE PYRENOMYCETES. 
(Plate XIII.) 
By Franz von Tavel. 
(Con tinued f rom page 123.) 
IV. — CUCURBITARIA PLATANI, U. S. 
Among the numerous fungi which came under our observation during 
this investigation, we gave special attention to a Cucurbitaria. It was 
found only on the fallen Platanus branches and then sparingly, so that 
our investigations were necessarily limited to the formation of the 
pycnidia. For the same reason it was impossible to ideutify the fun¬ 
gus. It is here designated as Cucurbitaria platani n. s., because from a 
purely practical stand-point the object of an investigation must have a 
name, and because neither Saccardo nor Winter mention a Cucurbitaria 
growing upon Platanus. 
The stroma of the fungus is circular and about 2 mm. in diameter. 
It lies under the bark, which becomes broken through by the perithecia 
and pycnidia. Generally several stromata stand close together. 
Twenty fruiting bodies, partly pycnidia and partly perithecia, stand 
in very irregular order upon a stroma. They are often very close 
to each other and frequently grow together. The pycnidia have very- 
irregular cavities and thick, intensely black walls. The basidia are 
filiform, the pycnidia spores extraordinarily small, cylindrical, and 
colorless. The perithecia are flask-shaped but of very irregular form 
and without a distinct neck or papilla. Their walls are also black 
and scarcely project beyond the bark. The asci are 8-spored, cy¬ 
lindrical, obtuse above and suddenly tapering into a short pedicel 
below. 
The spores are light brown at maturity, elliptical, a little smaller at 
the ends, and strongly constricted in the middle. The}" usually have 
six transverse septa, often more or less ; the number of the longitudi¬ 
nal septa is very variable. They are 18-25 /a. long by 9-11 ja. broad 
(Fig. 13.) 
The ascospores germinate rapidly even when they have been kept 
dry for a long time, but they behave very differently in water and in 
nutritive solutions. When sown in distilled water, sometimes all, and 
sometimes only single cells of the spore send out germ tubes which 
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