430 101. LYCOPODIACE^E. 



1. PILULARIA. Involucres solitary, nearly sessile, globose, 

 coriaceous, 4-celled. Cells containing bodies of two kinds ; 

 granules, and membranes containing minute grains. 



1. PILULARIA Linn. Pillwort. 



1. P.globulifera(L.}.E.B.52l. N. 393. Rhizome slender, 

 creeping, producing leaves and roots at regular intervals. L. very 

 slender, erect. Inv. slightly stalked, axillary, nearly spherical, 

 hairy. Margins of ponds and lakes. P. 



Order CI. LYCOPODIACE.E. 



Leafy plants with simple imbricated leaves ; or stemless with 

 erect subulate leaves. Fructification of axillary sessile capsules 

 with 2 or 3 valves and no ring, including minute powdery matter 

 or sporules. 



* Capsules not opening. 



1. ISOETES. Fructification inclosed within the swollen base 

 of the leaves. Sporules of two kinds attached to filiform 

 receptacles. 



** Capsules bursting. 



2. LYCOPODIUM. Caps. 1-celled, 2-valved, containing pow- 

 der; or 3-valved, containing 14 granules. 



1 . ISOETES Linn. Quillwort. 



1. I. lacustris (L.); 1. subulate roundish-quadrangular with 4 

 longitudinal jointed tubes. E. B. 1084. N. 381. R. vii. t. 1. 

 Rhizome a blunt tuber. L. slender, broad and flat at the base, 

 but elsewhere between cylindrical and quadrangular. Bottom of 

 lakes and ponds in hilly districts. P. VI. 



2. LYCOPODIUM Linn. Club-moss. 

 * Caps, all \-celled. Sporules like powder. LYCOPODIUM Koch. 



1. L. clavatum (L.) ; 1. scattered incurved with a filamentous 

 point, spikes stalked 2 or 3 together cylindrical, scales ovate- 

 triangular membranous finely incise-serrate. E. B. 224. N. 353. 

 St. prostrate, long. Branches short, ascending. Spikes on 

 long stalks, pale yellow. Scales on the stalks irregularly disposed 

 in whorls. Heaths. P. VII. VIII. Common Club-moss. 



2. L. annotinum (L.) ; 1. scattered lanceolate mucronate ser- 

 rulate, spikes sessile solitary terminal, scales roundish with an 



