%00
DOTHIDEA U lm i.
Elm-leaf Dothidea.
C la ss a n d O r d e r CRYPTOGAMIA FUNGI, N a t . O r d . HYPOX YLA ,
De Cand. Grev.
GEN ERIC CHARACTER.
“ Celluke (plures vel solitarice) in stromate immersoe, subrotundre, niicteo cereo-
farctce, demum ore simplici apertæ, absque proprio perithecia.
Cellules {several or solitary) immersed in a receptacle, somewhat round,
filled with a wax-like nucleus, at length opening by a simple orifice,
without a real perithecium.
S PEC IF IC CHARACTER.
D o t h id e a U lm i ; “ epiphylla, subroiunda, conjluens, convexa, cinereo-nigra, intus
nigra, cellulis albis, ostiolis granulæjhrmibus.”—F r i e s .
D. epiphyllous, roundish, confluent, convex, greyish-black, black within,
the cellules white, orifices granuliform.
D o t h i d e a Ulmi, Fries, Syst. v. 2. p. 555.
S ph æ r ia xylomoides, De Cand. FI. Franç. v. 2. p. 288.—Fjusd. Syn. p. oO.
S ph æ r ia U lm i, Duval, in Hopp. Bot. Tasch. I 8O9, p . 10 5 .—Fries, in Vet.
Ac. Handl. I 8I 6, p . 143.—Holl et Schmidt, Deutschl. Schmaem. No. 32.
S ph æ r ia Ulmaria, Sow. Fung. t. 374. f. 3.
S trom a to s phæ r ia Ulmaria, Crev. FI. Fdin. p. 359-
X yloma Ulmeum, Mart. Cr. Erlang. Jide Fries.
X yloma Ulmi, Purt. Midi. FL v. 3. p. 317.
Hab. On the dead leaves of various species of Elm (Ulmus) ; very frequent
in autumn and winter.
Receptacles from almost a point to nearly a quarter of an inch broad, roundish,
confluent, convex, of an iron-grey colour, originating beneath the
epidermis, which becomes cracked and torn, b u t is more or less persistent.
Within, they are black, and almost filled with cellules, of a sub-
globose form, those towards the surface becoming furnished with small
orifices, which resemble warts on the surface of the receptacle, as represented
at Fig. b. The cellules are white internally, and contain thecæ
of an elongated, Uhear, obtuse figure, inclosing oval sporidia.
The receptacles of this plant, as well as of the following
one, contain real cellules, or, in other words, the thecce and sporidia
are situated in regular-shaped cavities, which are destroyed
when the receptacle is broken up, and are not left entire, as
is the case wdth tbe compound Sphoerioe. In this respect, independently
of other equally important circumstances, both
of these plants differ from Dothidea Loniceræ (Lasiobotrys
Loniceræ of K u n z e , figured at t. 191. of this work.)
VGL. IV