276 THE AMERICAN NATURALIST. | (Vor. XXXIX. 
phyllous and cladosiphonic Lycopsida, opposed to the megaphyl- 
lous, phyllosiphonic Pteropsida. 
In his comparison of the gametophyte of Equisetum with that 
of Lycopodium, Jeffrey has overlooked a radical difference, to 
which Goebel ! has called attention, and which has been noted 
by other investigators. In the former genus, the gametophyte 
is dorsiventral, as it is in the ferns, and the archegonia originate 

Fig. 1, — A-C, young archegonia of Marattia douglasii; D-F, young archegonia of Egui- 
, basa l 
setum telmateia ; b, b 
cell of the archegonium. 
l cell; x, basal cell cut off before the isolation of the mother 
upon the ventral or shaded surface, the more or less conspicu- 
ously upright position being dependent upon light. The position 
of the archegonia upon the upper side of the prothallium is a 
secondary condition. 
In Lycopodium, the prothallium is radially constructed, the 
lobes being arranged equally about the upper part. The growth 
1 4 
Organographie der Pflanzen. Zweiter Theil, Heft II, p. 409. 
