tlie S.AV, and Central Highlands of Scotland, and S.AAA Ireland.—B. AI. :
The Grove, Island of Jersey. Near Hale End, Epping Forest, Essex;
Shiere, Surrey; Folltestone, K e n t; AA’est Downs and Henfield, Sussex ;
Shanklin, Luccombe, and Benchurch. Isle of AATght; near AATthiel, Cornw
a ll; Clevedon, Somersetshire; near AAteotton-uuder-Edge, Gloucestershire
; Colwall, Herefordshire; near Ayton, Cleveland, A’orkshire.
Island of Lismore, Argylesliire; Clova, Forfarshire. Dunkerron, co.
Kerrv.
6. L. am p h in eum Nyl. Lich. Soand. (1861) p. 32.—Thallus ad-
natfi, very tliiu, or subcrustaoeous, unequal, olive or brownish-green.
Apothecia small, concave, dark-reddish, the margin thickish ; spores
ellipsoid or ellipsoideo-ovoid, 3-septate and variously divided,
0 ,0 2 3 -2 7 mm. long, 0,009-0,011 ram. thick.—Cromb. Journ. Bot.
1874, p. 133 : Leight. Lioh. Fl. ed. 3, p. 29.— Oollema amphineum
Ach. ex Nyl. 1. c.
Differs from L. humosum in the more continuous and equal thallus,
and in the structure of the spores, and from L. subtile, of which it seems
a subspecies (Grevillea, xv. p. 12), in the more crustaceous thallus and
larger spores. The plant spreads thinly over the substratum, aud with
us is sparingly fertile.
Hab. On the ground, rarely on roots of old trees, in shady places in
maritime and upland tracts.—D tiir. Found only sparingly in S. and AV.
England.—B. AI.: Henfield, Sussex; Newlyn Cliff, Penzance, Cornwall;
Stroud, Gloucestershire ; Newbury, AVorcestershire.
7. L. m in u tis s im u lu F r. Sum. Veg. (1846) p. 1 2 2 ; Koerb. Par.
(1865) p. 423.—Thallus thinly membranaceous, minutely lobed,
smooth, olive-green or leaden-brown ; lobes imbricate, inoiso-orenate
a t th e margins. Apotheoia minute, concave, reddish-brown, th e
margin thin, entire, or sometimes a t length suborenulate; spores
oblongo-ovoid, irregularly murali-looular, large, 0,0 2 4 -0 ,0 3 0 mm.
long, 0,009—0,015 mm. th ick.— Oollema minuiissimum Fldrke,
Deufaoh. Lich. (1815) n. 99. Leptogium lacerum var. crenatum
Nyl., ex Carroll, Jo u rn . Bot. 1866, p. 22. Leptogium subtile f. lati-
usculum Nyl. ex Josh. Grevillea, iv. p. 43 ; Leight. Lioh. F l. ed. 3,
p. 29. Leptogimn sinuatum var. crenulatum Cromb. Jo u rn . Bot!
1 8 /4 , p. 336 ; Leight. Lich. Fl. ed. 3, p. 40. Leptogium fragrans
Mudd, Man. p. 46 ; Leight. Lioh. Fl. p. 30, pro p a rte . Oollema fra grans
T&y]. in M a ck .Fl. Hib. ii. p. 107.— B rit. Exs.-. Cromb. n. 107.
_ This species, little understood by British authors, looks like a diminutive
state of L . lacerum, though at once separated by the texture of the
thallus. From the closely allied L. subtile it is distinguished by the
more developed thallus and the larger spores. The apothecia, which are
numerous and crowded, are gyaleotiform and superficial.
Hab. On the ground, rarely on trunks of old trees, in upland districts
-D i s f r . Local and rather scarce in S., AV., and N. England, rare in s!
Heland.—B. AI.: Halstead, K e n t; Butler’s Holt, Buckinghamshire; near
Cir^cester, Gloucestershire; near Ayton, Cleveland, Yorkshire. Bantrv
CO. Cork. - ^
8. L. cretaoeum Nyl. Act. Linn. Soo. Bord. ser. 3, i. (1857)
p. 270 ; Syn. i. p. 120.—Thallus rosulato-lobulate or stellato-laoi-
uiate, olive-brown or dark-olive; the lobes unequal, crenate, almost
imbricate. Apotheoia small, nearly biatorine, concave or gyalecti-
form, pale reddish-brown, th e margin entire, paler ; spores ovoid,
;j_7_septate, with longitudinal septa, 0 ,0 2 2 -4 0 mm. long, 0 ,0 1 1 -
17 mm. thick.—Mudd, Alan. p. 4 5 ; Cromb. Lieh. Brit. p. 7 ; Leight.
Lioh. FL p. 32, ed. 3, p. 27.— Enchijlium cretaceuin Gray, Nat. A rr.
i. p. 398. Collema cretaoeum Sm. Eng. Fl. v. p. 210. lAchen
cretaceus Eng. Bot. (1800) t. 738.
This plant appears at first as minute, very thin, olive or dark stellce,
somewhat iniraorsed and distinct. These become more prominent, approximate
and confluent, till it attains the perfect state. I t is occasionally
.seen in an isidiomorphous condition. The gonimia are rarely moniliform.
The apothecia, seen only in the best developed specimens, are small in
the scattered, and moderate in the confluent rosulce.
Hab. On cretaceous and siliceous nodules in moist shady places in
upland tracts.—Distr. Confined to the Chalk and Oolite districts of S.
and AV. England ; probably iu its young state often overlooked.—B. AI.:
Near Follcestone, K en t; Plumptou and AVest Dean, Sussex; Reigate
Hill, Surrey ; Isle of W ig h t; Brighton Downs, Sussex ; near Northleach,
Gloucestershire; Stokesay, Shropshire.
9. L. microscopicum Nyl. Bull. Soo.
Bot. F r. iv. (1857) p. 9 2 0 ; Syn. i.
p. 122, t. 4. f. 17.—Thallus effuse, very-
minute, fruticulose, erect, branched,
olive-brown, dark-brown or b la c k ish ;
branches slender, elongato-papillate, u n equally
rounded, somewhat constricted
or attenuate a t th e base. Apotheoia
very minute, scattered, concave, pale
brown or brownish-red, th e margin
smooth, e n tir e ; spores ovoid or oblong,
3-5-septate, and murali-looular, 0 ,0 2 2 -
27 mm. long, 0 ,0 0 9 -1 4 mm. thick.—
Cromb. Journ. Bot. 1874, p. 336 ;
Leight. Lich. Fl. Suppl. p. 468, ed. 3,
p. 34.—B rit. E x s. : Cromb. n. 7.
In its earlier stages of growth this has
the appearance of a Sirosophon. The thallus
is cellular, and the gonimia are often
3-moniliform. Though resembling a minute
state of L. lophxum, it is distinguished
by its peculiar habit and the
Fig. 17.
form of the spores. I t is very rarely Leptoymm microscopicum Nyl.
fertile. On the thallus is occasionally Thallus, x 30. i. Seeseen
a parasitic Ohryzum described here- tion of apothecium. x30.
after. c. Three spores, x 500.
Hob. On slaty rocks, but chiefly on challi pebbles and calcareous walls,
E 2