12 Rhodora [JANUARY 
Gewüchse 2: 4. 1797. Mesophylla scalaris Dumort., Comm. 
Bot. 112. 1822.  Alicularia scalaris Corda; Opiz, Beitr. zur Naturk. 
1: 652. 1829. On rocks. Eastport, Maine (A. W. E., 1911). 
New to New England. Although Nardia scalaris is so abundant 
in northern Europe, only a few records of its occurrence in North 
America have been published. The writer is now able to cite the 
following localities for the species, several of which have already been 
noted elsewhere: ! Greenland, according to C. Jensen; Battle Harbor, 
Labrador, and Lantern Cove, Newfoundland (W'aghorne); Arichat, 
Cape Breton, Nova Scotia (0. D. Allen); Campobello Island, New 
Brunswick (Farlow); Dawson, Yukon (Williams); Yes Bay, Alaska 
(Howell); Juneau, Alaska (Brewer and Coe); Nanaimo, British Colum- 
bia (J. Macoun); Port Renfrew, British Columbia (Mss Gibbs); 
Mt. Ranier, Washington (0. D. Allen, Foster, Flett); Olympic Moun- 
tains, Washington (Frye). The specimens from Nova Scotia and New 
Brunswick grew on low cliffs by the sea, and those from, Eastport were 
collected in a similar habitat. The plants formed dense mats, 
scarcely ten feet above high water mark and only a few feet below the 
edge of the woods. 
The species is dioicous and most of the material from North America 
is completely sterile. The shoots are normally prostrate but become 
suberect when growing in compact masses. On account of their 
rotund undivided leaves, usually imbricated and concave, the plants 
bear a considerable resemblance to such species as N. crenulata and 
Jungermannia sphaerocarpa. They can be at once distinguished, how- 
ever, by their small but persistent underleaves, which are lanceolate 
or subulate in form and taper out to slender points. These under- 
leaves show clearly, even when a shoot is viewed from one side, be- 
cause they are not closely appressed to the stem but spread out from 
it at the base almost at right angles. "The leaf-cells have small but 
distinct trigones and each encloses a small number of large and 
glistening oil-bodies with a smooth surface. ‘These peculiarities will 
also assist in distinguishing the species. 
The closest relative of N. scalaris is N. Geoscyphus (DeNot.) Lindb., 
known in New England from New Hampshire and Massachusetts.? 
This species being paroicous is frequently fertile. ‘The plants rarely 
occur in dense mats, so that the shoots are usually prostrate and 
1 See especially Macoun, Cat. Canadian Pl. 7: 12. 1902. 
2 See Evans, Ruopora 9: 57. 1907. 
