347 
ANTHOCEROS DICHOTOMUS IN BRITAIN. 
By Symers M. Maovicar. 
ANTHOCEROS DicHoTomus Raddi in Act. Acad. Sien. ix. p. 289, 
t. 4 (1808). A. polymorphus var. y dichotomus Raddi in Opuse. 
scientif. di ait li. p. 859 (1818) 
Mon Fronds prostrate, with short irregularly divided 
sarentat in 4 Eh fertile plant ; segments in the sterile plant dicho- 
omous, narrow, linear or oblong, channelled, with the margins 
ascending and sinuate, carinate postically, and with descending 
ee at intervals proceeding from the costa; the costa without 
oot-hairs or almost so, but which Sessa. "Mavclipal later on the 
oe ‘‘ Costa 3-4 the width of the segment, 6-10 cells thick, the 
lamina mostly 2-stratose, involucre ieee mm. wide, often enlarged 
at the irregularly 2-4-lobed mouth.” ‘‘ Capsules erect or slightly 
curved, 7°5-15 mm. long, often thickened towards the apex, spores 
yellow, becoming yellowish brown, rounded-tetrahedral, almost 
wholly smooth on both faces, 42-60 p in maximum diameter, 
pseudo-elaters yellowish, of 1-4 irregular elongated cells, geniculate, 
variously contorted, often branched.’ 
T aracters in inverted commas are taken from the admir- 
able Hepatice and Anthocerotes oh Doge ttre of Dr. Marshall A. 
Howe, who has examined a spec f the species from Raddi’s 
herbarium, the characters of the latter cea being drawn from the 
specimen. The involucre is single, though Nees appears to think 
that they may be Saray a eminate. In the few spec which I 
have mr the cnpareaaihe of eRe onine they are 
ubers on the under side of the costa will a alone distinguish 
the tubers will be seen to be Se "The saber seem to be com- 
paeitiecly Meiel completely gle apes in the English plant they 
are § sually evident. The ch hannelled dichotomous costate 
segments, cape beneath, the convexity penne well seen in section, 
differ from that of our ur other species. On section also the — of 
large air cavities will distinguish it from A. punctatus and A, Stableri. 
In fruit, the black echinate spores of these last — a once 
se te them. A. laevis a flat fronds with rounded segments, 
which are not carinate ben 
The history of the discovery of this species in Britain is rather 
curious. When examining a collection we Hepatice which belonged 
to the late Alex. Croall, I found an unnamed Anthoceros in fruit, 
which appeared different from any of our known species. The 
locality was given, but itis sufficient to state that it is in the neigh- 
bourhood of Dawlish, Devonshire. the date being 7 AST? aud..the 
Blent gathered by Croall. I sent a specimen to rr Stephani, 
who thought it was a new species, but could not oi a definite 
