GYROTHYRA | 91 
dry, attached spiro-radially to а basal disc composed of large 
hyaline cells, flexuous, contorted, or spiral, when moistened— 
always with a spiral twist at the apex ; foot of sporogonium form- 
ing a more or less goblet-shaped “ involucellum " ; seta 114-2 cm. 
long; elaters bispiral, very rarely trispiral, acute or subobtuse, 
210-420 их 12—15 и; spores about 12 и, minutely papillate. 
Exsicc. Hep. Am. 184. 
Near Eureka, Humboldt Co., June, 1896 (no. 1026); collected 
also by Prof. John Macoun (herb. Underwood), on earth in a 
brook, Burrard Inlet, British Columbia, April 6, 1889, and on rocks, 
British Columbia, April 29, 1880; and by А. А. and E. Gertrude 
Heller, near Montesano, Chehalis Co., Washington (June 7, 1898, 
no. 4289). 
The leaves of the British Columbia and Washington plants 
stand with their margins more often erect than in the Californian 
specimens, upon which our description and figures are based. Іп 
the sterile condition, Gyrothyra somewhat resembles the larger 
forms of Nardia scalaris—also collected by Macoun on Vancouver 
Island (Can. Hep. 80)—but can readily be distinguished by the 
margined, linguiform, more translucent leaves, and by the bifid 
underleaves. 
The ф bracts, though more or less apparently paired, are на 
strict sense alternate like the cauline leaves, and a single unpaired 
leaf is sometimes found to occur inside the pair we have described 
as the uppermost. : 
It should be remarked that the actual dehiscence of the capsules 
has not been observed, but the extremely long valves, which on 
being soaked out take easily a position strongly suggestive of the 
paring of an apple, the spiro-radial attachment to the basal disc, 
the never failing spiral twist of the valve-apex, and the spiral lines 
readily discernible on the surface of the embryo capsule (fig. 10) 
make, in our judgment, the induction that the dehiscence is spiral 
50 safe and certain that we have felt no hesitation in so describing 
it and basing the generic name upon this character. The absence 
of thickenings in the walls of the cells of the capsule valves. В 
Noteworthy. Schiffner states* of all the Jungermanniaceae akrogy- 
"ае: “ Die reife Kapsel besitzt eine aus 2 bis mehr Zellschichten 
* Engler and Prantl, Nat. Pflanzenfam. 13:71. 1893. 
