Liverworts or Hepatics 



The antheridia are spherical, in the axils of overlapping leaves 

 which form short rigid branches. 



The perianth is oval to obovate, flattened at the mouth, which 

 is fringed, toothed or entire. The spore-case is spherical to 

 ovoid-oblong on a short stalk (seta) splitting nearly to the base 

 into four parts. The spores are covered with spines. The elaters 

 are once to thrice spiral. 



The generic name is a diminutive of the Latin porus, a pore. 

 Its significance is not evident. 



Porella platyphylla, (L.) Lindle. Plant (gametophyte). 

 Stems 2 or 3 inches long, prostrate, rigid with the tips bent 

 upward; i to 3 times regularly or irregularly pinnate; root-hairs 

 in tufts at the base of the under-leaves. 



View of upper surface of 

 tern with two leaves. 



Two leaves showing lobe 

 and lobule 



Under view of stem. 

 Porella platyphylla. 



Leaves. Deeply two-parted, dorsal lobes overlapping in two 

 rows so as to conceal the stem, obliquely placed relatively to the 

 stem, oval to oblong, apex obtuse, toothed or entire. Ventral 

 lobes oval to oblong obtuse, diagonally pressed to the surface of 

 the upper lobes; margins recurved and entire or with a single 

 tooth at the base; under leaves tongue-shaped, parallel with the 

 stem, margins recurved, decurrent, entire, or sparingly toothed 

 at the base. 



Name. The specific name platyphylla from the Greek TrXctrw, 

 flat, and <f>v\\ov, a leaf, describes the prostrate habit of the plant. 



Perianth. Ovate, inflated, narrowed above, margin toothed 

 with a notch on one side. 



Veil (calyptra). Persistent, globose, splitting above. 



Spore-case. Pale yellow-brown on a short pedicel, splitting 

 into four, often irregular valves ; elaters bi-spiral. 



Spores. More or less spiny. 



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