Isidia—Coral-like papillæ with dark apices.
Medulla—The usually colourless internal tissue.
Mnriform—With transverse and irregular longitudinal divisions.
Nuclear—Roundish, with an apical pore.
Ostiole—An apical jiore.
Parapht/ses—Slender filaments among the thecæ.
Peridioid—Roundish, without a pore.
Peridium—The hypothecium of a peridioid apothecium.
Podetium—Aw erect cylindrical thallus terminated by the fruit.
Polari-hilocular—With a loculus at each end.
Pi/cnides—Oonceptaclea bearing stylospores.
Pyrenium—The hypothecium of a nuclear apothecium.
Scyphus—A dilated cup-shaped fruit borne on a podetiuni.
Soredia—Vo-wiery masses of gonidia and hyphæ.
Stylospores—Asexual spores.
'Plialamium—The paraphyses.
Thecec—The spore-sacs.
Thecium= Hvmenium.
CHEMICAL REACTIONS.
The solutions employed a re:—(1) Hydrate of potash, denoted by the
symbol K, and composed of equal weights of caustic potash and \vater ;
(•>) Hypochlorite of lime, denoted by' CaCl, and composed of chloride of
lime and about half its weight of water ; (3) Iodine, denoted by I, and
composed of iodine 1 grain, iodide of potash 3 grains, and distilled water
j oz. For the sake of brevity, symbols are employed to express the
reactions. The explanation of a few examples will be found sutticient to
explain the rest. Thus CaCl-t-crimson indicates the immediate production
of a crimson coloration upon the application of the solution
CaGl. CaCl— means th a t no reaction occurs with this reagent.
Kf-|-yellow mean.s a faint yellow reaction with solution K. The
reaction of the cortex is placed above th a t of the medulla; thus
means th at the reaction of the cortex is yellowish and
that of the medulla orange. K(CaCl)-f-violet means th a t K alone
gives uo reaction, but when it is foilowed by- the application of CaCl
a violet colour is produced. On the other hand, the reaction given by K
may be neutralized by the addition of CaCl, in which case it is expressed
by K-I-(CaCl) — . A more or less fuscescent colour produced by K
or CaCl is disregarded, as not being a true reaction, and has the negative
sign.
s r m p m s o f t h e f a m i l i e s , t r i b e s , a n d
G E N E R A OF B R I T I S H L IC H E N S . ’
FamHy I EPHEBACEI Nyl. ThaUus slightly turgid when
moist, cellular w ith in ; gonimia tunicatod, no t moniliform.
Tribe I . S IE O S IPH E I Nyl. ThaUus filamentoso-fruticuloso;
aonimia variously c o n n a te : apotheoia biatorine or locideine.
1. Gonionema Nyl. ThaUus flbriUosc, tubuliform; gonimia connate
in one continuous series; apotheoia biatorine, with simple
2 Spilonema Born. Thallus frutioulose, cylindrical, often pnl-
vmate_i gonimia connate in transverse la y e rs : apotheoia Iccideino,
w ith simple or 1 -septate spores and articulate pa rap h y se s; spermo-
gones w ith jointed sterigmata and shortly cylindrical spermatia.
Tribe I I . PY EENOPSEI Nyl. Thallus th in ly granulóse, ru h ri-
p y rL To a rp ras^””™ '^ ' apotheoia lecanoriue or
3. E uopsis Nyl. Thallus g ra n u la to -a re o la te ; gonimia simple
or nodulose : apotheoia leoanorine, w ith articulate paraphyses and
simple spores; spermogones w ith simpUsh sterigmata and minute
oMong spermatia.
4. P y r p o p s is Nyl. Thallus granulato-areolate or subsquamu-
lose ; gonimia simple or nodulose: apotheoia pseudo-pyronocarpons,
m th simple paraphyses and spores; spermogones w ith simplish
sterigmata and minute oblong spermatia.
Tribe I I I . p S IO P S ID E I Nyl. ThaUus either frutioulose, with
seriate gommia; _or squamuliform or granulóse, with subsolitary
g o n im ia : apotheoia pyrenoearpous.
_ Subtribe E PH E B E I Nyl. ThaUus fruticuloso, intricate, dice-
oipna or moncBcious; gonimia nodulose: apotheoia pyrenoearpous,
With or w ithout paraphyses.
5 Ephehe F r ThaUus dioecious ; gonimia 2 - 4 in each n odule:
apotheoia in thalUne incrassations, with simple or 1 -3 -sep ta te spores
and no pa rap h y se s; spermogones w ith simpUsh sterigmata and
shortly cylindrical spermatia.