186 Rhodora [OCTOBER 
he separated off, as distinct species, M. conjugata, M. hamata, and M. 
myriopoda, largely on the basis of characters drawn from the structure 
of the thallus, the distribution and peculiarities of the marginal and 
postical cilia, and the nature of the inflorescence. He restricted the 
name M. furcata to what he described as the commonest of all European 
hepaticae but stated that he had never seen typical specimens of this 
species from North America. To M. conjugata, on the other hand, 
the only one of his new species which need now be considered, he 
ascribed a wide distribution on both sides of the Atlantic. Since this 
time the majority of writers, including such recent authorities as 
Stephani? and C. Müller? have accepted Lindberg’s statements with 
regard to the absence of M. furcata from North America and have 
consequently considered M. conjugata as our common representative 
of the genus. In 1892, however, Miss Boatman * recorded M. furcata 
from various localities in North America, extending from North 
Conway, New Hampshire (James), into Mexico, and Underwood ? 
soon afterwards published similar observations independently. On 
the basis of these records the species ought properly to have been 
included in the writer's Preliminary List of New England Hepaticae,’ 
but it was omitted because Underwood himself expressed some doubt 
as to the correctness of the determinations, most of which were based 
on thallus characters only. Apparently the specimens quoted above 
represent the species clearly, so that M. furcata may now be definitely 
reinstated as a member of our flora. Equally clear specimens have 
been examined also from Indian Brook, Cape Breton (G. E. Nichols), 
and from Onteora Mountain, New York (Miss Vail). 
All writers agree that M. furcata and M. conjugata are very closely 
related. In both species the costa presents the same type of structure, 
being bounded above by two rows of cortical cells and below by from 
three to five rows. Lindberg finds the most important difference 
between the two plants in the inflorescence, M. furcata being dioicous 
and M. conjugata autoicous, but he also calls attention to differences 
in the structure of the thallus, to which he attaches considerable import- 
ance. In M. furcata, the less robust of the two, the thallus is said to be 
1 This species was first published in Acta Soc. Sci, Fenn, 10: 495. 1875. 
? Bull. de l'Herb. Boissier 7: 941. 1899. 
? Rabenhorst's Kryptogamen-Flora 6: 349. 1908. 
4 Bull. De Pauw Sci. Assoc. 1: 3. 1892. 
5 Bull. Torrey Club 19: 301. 1892, 
6 RHODORA 5: 170-173. 1903. 
