1909] — Evans,— Notes on New England Hepaticae,— VII 191 
themselves are about 8 » in diameter and show two spirals. In P. 
Fabroniana, on the other hand, the inner layer of the capsule-wall is 
without local thickenings; the elater-bearers are only 5-8 џи in diameter 
and number about 100; while the elaters themselves are 10-12 y in 
diameter and show three or four spirals. The differences in the 
structure of the capsule are fully discussed by Jack.! 
The relationships between P. Neesiana and P. epiphylla are very 
close indeed, both thallus and capsule showing the same structure in 
the two species. ‘There are, however, two important differences 
between them. In P. Neesiana the inflorescence is dioicous, and the 
involucre is in the form of a short but complete sheath with an irregular 
margin. In P. epiphylla the inflorescence is monoicous (paroicous), 
and the involucre is represented by a short flap of the thallus on the 
basal side of the sporophyte. P. Fabroniana agrees with P. Neesiana 
in being dioicous and in developing a tubular involucre, but the latter 
is long and extends beyond the calyptra, whereas in P. Neesiana the 
calyptra extends beyond the involucre at maturity. ‘The differences 
just noted are very clearly shown by C. Müller ! in a series of schematic 
figures? It will be seen from the foregoing statements that sterile 
specimens of Pellia with bands of thickening in the internal cells of the 
thallus are quite indeterminable. 
5. CEPHALOZIELLA ELACHISTA (Jack) Schiffn. Lotos 48: 338. 
1900. Jungermannia elachista Jack; Gottsche & Rabenhorst, Hep. 
Europ. 474 (with figures). 1873. Cephalozia  elachista | Lindb. 
Acta Soc. Sci. Fenn. 10: 502. 1875. On a decayed stump in a bog; 
Reading, Massachusetts (C. C. Kingman). Not before recorded for 
America. Widely distributed in Europe but apparently rare. This 
delicate little species seems to be confined to bogs and is characterized 
primarily by an autoicous inflorescence and by distant, sparingly 
dentate leaves. The plant is pale green in color and the prostrate 
stems are sparingly branched. ‘The deeply bifid leaves are almost 
transversely inserted and tend to spread widely from the axis. ‘Their 
lobes are slender and sharp-pointed, usually from four to six cells long 
and from two to four cells wide at the base, and they are frequently 
inflexed at the apex. The leaf-cells have a smooth cuticle and are 
thin-walled; in the middle of the lobes they measure 19-24 и in length 
1 Flora 81 (Ergánz.-Band): 1-16. pl. 1. 1895, 
2 Rabenhorst’s Kryptogamen-Flora 6: 369. /. 218. 1908 
