62 JUNGERMANNIALES 
Marchantia Oregonensis was described by Herr Stephani in 
1891 (Bot. Centralb. 45: 203) from ¢ plants collected by Roll on 
Mt. Hood. The only distinctive character emphasized is a reni- 
form irregularly dentate and spinose appendage to the postical 
scales. Іп а portion of the original plant communicated by Herr 
Stephani to Professor Underwood, we have been able to detect a 
few such scales immediately bounding the costa at the apical sinus, 
but there are also oblong or linguiform, obtuse, entire scales toward 
the margin as in М. polymorpha; as we have observed quite 
similarly appendaged scales at the apex of the costa in European 
specimens of M. polymorpha (е. g., Rab. Hep. Eur., no. 6; Мазза 
Hep. It. Ven. Exs., по. 21) and also in American specimens, we be- 
lieve that this peculiarity has no specific significance. These ap- 
pendages are usually of a violet or brownish color and are formed 
by a more or less pronounced narrowing of the scale accompanied 
by a slight twisting or convolution in the zone of contraction. 
Order II. JUNGERMANNIALES. 
Gametophore varying in different genera from a wholly leafless 
thallus, with or without а midrib but without other differentiation 
of tissues, to a cylindrical leaf-bearing stem. Root-hairs always 
with smooth walls. Stomata wanting. Sexual organs usually in 
groups, often on more ог less modified branches, yet never ОП 
special stalked receptacles, rarely immersed. 
The first division of the fertilized egg transverse, the lower of 
the two cells usually taking no further part in the development of 
the embryo.* Sporogonium provided with foot and seta, the latter 
commonly much elongated ; calyptra ruptured. Capsule nearly 
always opening by four valves. Sterile cells always accompany" | 
ing the spores, usually developed as elaters.+ : 
The order Jungermanniales comprises the two somewhat arti- 
ficial families, the Metzgeriaceae (see below) and the Jungerman- 
niaceae (see page 82). 
ха ұрт "rena "LEST ыш ‚ЫЫ 
i See Campbell, The Structure and Development of the Mosses and Ferns, 7% 
1895. 
T Among the Californian 
eral points of contact with the 
of somewhat immature capsules are studied. Тһе sterile cells are here starch-ladem, 
are destitute of spiral thickenings and become disorganized or inconspicuous by the m 
he spores are fully ripe. 
genera, the sterile cells in Sphaerocarpus (which has er 
Ricciaceae) may be easily overlooked unless the conten, 
