20 Evans: HeEpatTICAE OF PUERTO RICO 
currence in America.* With regard to D. hamatifolia it should be 
stated that no American stations for the species have recently been — 
cited with any degree of certainty and that the American specimens — 
quoted in the Synopsis Hepaticarum + undoubtedly belong else- | 
where. *Schiffnert reports, nevertheless, that specimens of a — 
Drepanolejeunea identical with this species or at any rate very close i 
to it occur in Schwanecke’s collection mixed with /arpalejeunea ; 
patentissima, and it is possible that these were the plants determined iH 
by Hampe and Gottsche. A fourth species, D. subulata, has H 
recently been described by Stephani, likewise from Schwanecke’s : 
collection. It appears probable that this species is based on the — 
“ Lejeunia tenuis” of Hampe and Gottsche’s list, although this is — 
not definitely stated by its author. 
The collections of Puerto Rico Hepaticae made by A. A. Heller i 
and by the writer include ten species of Drepanolejeunca, all found — 
in the Luquillo Mountains. Of these ten species D. inchoata and — 
D. subulata have already been recorded from the island, four of the i 
other species, D. Araucariae, D. bidens, D. crucianella and D. im- i 
fundibulata, are known from other parts of tropical America, while : 
the remaining four are apparently undescribed. Of the two re- i 
corded species D. znchoata has a wide distribution in South America ? 
and the West Indies, while D. suéu/ata is known from Puerto Rico — 
only. It will be seen therefore that fifty per cent. of the species — 
known with certainty from the island seem to be endemic, a ratio q 
which will doubtless be reduced by careful exploration of the — 
neighboring islands. 
In all the Puerto Rico species of Drepanolejeunea the lobule is 7 
constructed on essentially the same plan as in Leptolejeunca sten-— 
i 
ophylla and L. hamulata. This type of lobule is characterized by q 
a peculiar curved cell or tooth at the apex, which assists mate- — 
rially in forming the opening into the water-sac of the leaf. At ' 
the base of the tooth on the side toward the axis there is present : 
a slight depression or notch in which a unicellular thin-walled and — 
hyaline papilla is situated. The terminal cell curves outward, — 
— 
* Hep. Amaz. et And. 192. 1884. 
7 P. 344. See also Stephani, Hedwigia, 29: 71, 18go. 
_ £Engler’s Bot. Jahrb. 23: 591. 1897. 
coming into contact with the postical surface of the lobe and some- : 
