—35- 



long decurrent, the wing sometimes longer than the free portion, and 

 usually sharply dentate. Perianth ovate, the lips subentire, and usually 

 plane. On moist rocks, and base of trees in deep woods. Common on the 

 Pacific Coast, but rare in the East. Has been collected in Connecticut, 

 Ohio, Texas, New Mexico, Montana and Idaho. Our illustration does not 

 show the decurrent wings of the underleaves. 



Fig. 5. Porella platyphylla 

 (L.) Lindb. 



B, Stem, upper side, showing 

 perianth and emerging cap- 

 sule. 



C, Stem, under side, showing 

 ventral lobes and under- 

 leaves. 



(The leaves are shown too 

 far apart. They should be 

 more closely imbricated.) 



D, Section of perianth length- 

 wise. 



E, Capsule: 



F, Leaf, showing lower lobe. 



G, Part of plant, showing male 

 branches. 



5. Porella PLAT yphylla(L.) Lindb. Fig. 

 5. {Jiingermannia platyphylla'L,. J.platy- 

 phylloidea Schwein. Madotheca platy- 

 phylla Dumort. Porella thuja Lindb.) Dull 

 or with a slight lustre, yellowish to dark 

 green, rigid; 1-3 pinnate, 3-8cm. long, in dense 

 mats ; dorsal lobes of leaves closely imbricate, 

 usually appressed, obliquely-ovate, obtuse, 

 upper margin subentire ; ventral lobes ovate 

 to oblong, obtuse, length about | the width of 

 the dorsal, margins recurved, scarcely decur- 

 rent; underleaves close together, nearly orb- 

 icular to oblong, margins reflexed, long de- 

 current: perianth oval, narrowed above, the 

 mouth dentate or ciliate. At base of trees and 

 sometimes on logs and rocks. Very common 

 ea^t of the Mississippi, and has been collected 

 in Idaho, Wyoming and British Columbia. 

 The American plants are mostly of the form 

 known as Porella thuja, though the European 

 form, P, platyphylla, is also found. 



6, Porella navicularis (L. and L.) 

 Lindb. Fig. 6. {Madotheca navicularis 

 Nees.) Glossy, brownish or yellowish-green, 

 large; stems bipinnate, procumbent in mats 

 or subpendulous: dorsal lobes densely imbri- 

 cate, closely wrapped about the stem when 

 dry, giving the dried plant something of a 

 cord-like appearance, apex recurved ; ventral 

 lobes ovate, obtuse or rarely acute, margins 

 entire and decidedly recurved, length about 

 Yo. the width of the dorsal lobe, sometimes a 

 Fig. 6. Porella naviciUaj'is little more than half; underleaves imbricate, 

 (Lehm. and Lmdenb) Lmdb. a ^ ^^ • ^■ 



A, Underside showing leaves quadrate-oblong, margms entire, recurved, 

 and underleaves. long decurrent; perianth broadly obovate, lips 



B, Leaf, showing dorsal lobe, denticulate to crenulate-dentate becoming 



