138 LEJEUNEAE OF THE UNITED STATES AND CANADA 
The validity of Z. Austini, so far as the specimens from the a 
United States are concerned, is recognized both by Underwood and 
by Stephani. The latter author first referred it to the subgenus 
Eu-Lejeunea, but at present considers it a Chellolejeunea. With it — 
he compares his Zu-Lejeunea Underwoodii, from Florida, a plant 
which he is now also inclined to place in Cheilolejeunea. It is evi- 
dent from the above statements that Z. duriuscula, L. Austini and. 
L. Underwoodu are all considered distinct species by Stephani. 
The writer has examined all the specimens which Lindberg re- 
ferred to L. Austini with the exception of those from Guiana. He 
has also examined the specimens of Z. Underwoodii distributed by . 
Underwood and Cook and those of Euosmolejeunea duriuscula in 
Hepaticae Spruceanae, collected near Pará, in Brazil. All of these 
plants show female flowers without perianths, and there are no 
male plants among them. Asa result of this study it would ap- 
pear that all of these specimens are referable to the same species, 
for which the oldest available specific name, “ duriuscula," should 
be retained. The differences stated by Stephani in his published — 
papers and in his manuscript notes are not always apparent and 
seem hardly sufficient to separate the species. He states, for eX- 
ample, that Z. Austin! has much smaller leaf-cells than Z Under- 4 
woodii, and that the lobule of the latter species is inflated and has 
an arched keel, whereas in Z. Austini the lobule is not inflated 3 
and the keel is approximately straight or concavely arched. He 
a 
states also that the bracteole is free in Z. Underwoodii and slightly 
connate on one side in Z. Austini. The first of these differences — 
p 
does not hold, since the cells of Z. Austini average fully as large ; 
as those of L. Underwoodii. The second difference is unreliable, 
because convexly arched, straight, and concavely arched keels may | 
often be found on a single stem, and the degree of inflation de- — 
pends largely upon the degree of development. The third differ- 5 
ence is at best inconstant as the bracteole is uniformly free in the - | 
specimens of L. Austini examined by the writer. Stephani has - 
published no descriptive notes on Euosmolejeunea duriuscula but — 
has kindly furnished a drawing of this species made from the type 1 
material. This agrees essentially with the specimens distributed a 
by Spruce. In reducing L. Austini and L. Underwoodii to synon- | 
ymy the writer regrets differing from so eminent an authority aS ， 
