288 BRYOLOGY OF NEW. ZEALAND. 
i. Pterygophylium dentatum (H. f..& W.) Mitt., M. austr.-amer. in 
Journ. Linn.:Soe., Bot., xii, p. 397 (1869). 
Syn. Hookeria dentata* H. f. & W. in Lond. Journ. of Bot., ill, 
550 (1844); Handb. N.Z. Fl. 495. H. nigella H. f. & 
W,, FL N.Z. ii, 124; Handb. NZ. ‘Fl, loe. te : Bleryoopt yl- 
lum nigellum Jaeg. Adumbr., ii, 947. he at 
petiolata Col. in, ‘Trans. N.Z. ‘Tnst., Xvili, ae (1886). H. 
ramulosa Col. op. cit., p. at a subsimilis Col. op. cit., 
p. 2383. H. obtusata Col. op , p. 233. H. curviseta Col. 
fia it., p. 2od. Hepntictns yolephatta si in Hedwig. 
xli, 124 (1902). Hepaticina parvula C.M. eit., p. F295. 
Hepaticina pseudo-obscura C.M. op. et loc. ett: -Hepaticina 
nanocaulis C.M. op. eit. p. 126. Hepaticina Zuerniana 
C.M. op. et loc. cit. ; 
P. dentatum grows in very wet places, is usually of a dark nua 
or blackish colour, generally turning quite black with age. The leav 
when old are often difficult to soak out. The large, obovate- Ba 
leaves of all species of this genus are known from the remainder of 
the Family by the large hexagonal cells, single nerve, and absence of 
border (the reel smaller cells of Disticho phylum microcarpum, 
becoming quite minute at the margin, separate it at once). The nerve 
tapers away pper part, and is frequently orth forked 
above; it always ceases at some distance below x. The eells 
are very lax, pellucid and thin-walled, in the upper part very regu- 
larly eer and with collenchymatous thickenings at the angles, 
which, owing to the transparency of the ells frequently give the 
appearance of fiderneliaiar spaces. The marginal bet especially in 
the region of the apex, are usually very mien a than the inter- 
is oe ulate; in addition to this the margin is usually more 
or less strongly, coarsely toothed, each tooth in some plants formed of 
o or three cells, of which the terminal one may be more or less 
distinetly spiniform. 
The plants are iba ana fertile, but the fruiting characters do 
not give any constant distinctions betwee n the forms. The seta is 
hen 
sule is often somewhat tubercular at the base where it joins the seta. 
The calyptra is glabrous, somewhat coriaceous, not fimbriate but 
sometimes slightly Ceca at base; the lid has a straight beak, vari- 
able in length. 
I have e = perwbee the types of the various species described by C. 
Mueller and give the above selon vn they are all merely forms 
ot the one hihi peaiee sw type 
e specific name ‘“‘denticulata,” as I have shown elsewhere, is 
—— a slip, copied probably by most authors from C.M. Synopsis ii, 
