1899] DEVELOPMENT OF CRYPTOMITRIUM 121 
forward margin. In Cryptomitrium the receptacle is a branch 
system, such as Leitgeb attributes to Marchantia and one or 
two other genera. This fact alone would be enough to out- 
weigh all the minor external characters referred to, were it not 
for the fact that, although Leitgeb puts Fimbriaria in the same 
type as Duvalia, Campbell (0. cé¢.) found that the receptacle 
of Fimbriaria Californica belongs to the ‘‘ Composite,” or branch- 
ing type. 
While one hesitates to criticise the classical work of Leitgeb, 
the quality and accuracy of which is for the most part remark- 
able, it does not seem reasonable that plants resembling each 
other as closely as Cryptomitrium and Duvalia should differ 
so much in respect to the growth of their receptacles, to say 
nothing of the fact that species of the same genus, Fimbri- 
aria, should also have this difference. It would seem more 
probable that Leitgeb was mistaken. Probably if one should 
carefully examine Duvalia and also the species of Fimbriaria 
which were studied by Leitgeb, it would be found that these too 
have as many growing points as there are groups of archegonia. 
Should this not be the case the apparent close relation between 
sa Cryptomitrium would be Only. apparent, and the 
oc oe perhaps, have to be considered more nearly 
cary farchantia, and Fimbriaria Californica could then no 
b€ considered as a Fimbriaria, for the difference in the 
‘wo kinds of receptacles is too great to occur within the same 
genus, | 
L ~ 
ELAND STANFORD JR. UNIVERSITY. 
