282 
PEEKS : BRITISH AND FOREIGN. 
162. PILULARIA, Linn. 
Plants with filiform leaves, from a creeping rhizome under 
water. Sporangia ( conceptacles ) radical (at the base of the leaves 
on the rhizome), globose, coriaceous, 2— 4-celled, 2-4-valved, each 
Genus 1 62. — Plant, natural size. No. 1. 
cell containing different kinds of bodies : — 1. ( Anther idangia), 
consisting of vesicles containing many minute granular spores ; 
2. (Oophor idangia), each containing a single large spore. 
1. P. globulifera, Linn. ; Willd. Sp. PI. 5, p. 535 ; Bolt. 
Fil. t. 40 ; Sclik. Crypt, t. 173 ; Eng. Bot. t. 521. — 
Europe and Britain. 
i 
163. ISOETES, Linn. 
Plants with awl-shaped leaves, from a thick creeping rhizome 
under water or out of water. Sporangia ( conceptacles ) borne in the 
