Lit
I :îi
f
i'li I
r
It must be confessed, tbat, amidst tbe variety of pleasures
experienced by tbe naturalist wbose feelings are alive to tbe
wonderful structures be is daily contemplating, be is occasionally
sadly perplexed in bis pursuit. Objects rise up of doubtful
affinity, and produce a kind of pain in sucb minds as are intent
upon the accuracies of systematic arrangement. The subject
of the present description is an instance of this. Originally
published as a Sphæria by P e r s o o n , it became a Polystigma
in the memoir composed by D e C a n d o l l e on that
genus, in the Mémoires du Museum. M. F r i e s has subsequently
placed it among the Dothideæ ; from which, again, I
have presumed to remove it. M. F r i e s has indeed observed,
that it has a near affinity to Sphæria, but that, in consequence
of its habit, he has arranged it with his Dothidea {Polystigma
nobis) rubra nnà fulva. After making a most careful analysis
of every part, I am inclined to think it should still remain
among the true Sphæroideoe, and that I was wrong in the Flora
Edinensis, where I considered it a Polystigma, in common with
D e C a n d o l l e . That a real receptacle is present, cannot be
doubted, as the whole may be easily removed from the culm, as
is indeed shewn in the figure published by N e e s . (I have not
seen that given by P e r s o o n . ) In this respect, it differs essentially
from Polystigma rubrum and fulvum, whose receptacle
is innate, and formed by a modification of tbe substance
of the leaf on which they grow. The perithecia in our plant
are in no respect different from those of the carnose stipitate
Sphoerioe {Xylariæ nobis) ; their near affinity being farther
confirmed by the gelatinous mass of thecæ escaping spontaneously
from the orifices. On the other hand, to the naked
eye, and without dissection, scarcely any one would think of
separating this curious plant from Polystigma rubrum and
fidvum.
Fig. I , 1. St. typhina, natural size. Fig. 2. An entire plant. Fig. 3. A portion
divided transversely. Fig. 4. A small portion in an old state, with fu ll-
sized perithecia. Fig. 5. A portion in which the perithecia ai'e divided transversely.
Fig. 6. A perithecium divided, file d with thecoe. Fig, 7. Thecce.
Fig. 8. Sporidia; magnified.