THE ANTHOCEROTE.E 



135 



In A. fusifoniiis they are longer and more symmetrical than in 

 A. hevis, and in one group of the genus, according to Gottschc/ 

 the elaters, which consist of a row of five to six cells, have a 

 distinct spiral band as in Dendroceros. Leitgeb " thinks, how- 

 ever, that this group is more nearly related to the latter genus 

 than to Anthoceros proper, inasmuch as in addition to the 

 peculiar elaters the epidermis of the capsule has no stomata, 

 which arc always present in typical species of Anthoceros. 



If the epidermis from the young capsule is examined it is 

 seen to be composed of elongated narrow cells much like those 

 in the epidermis of elongated leaves of Monocotyledons. In 

 the older parts some of these cells cease to elongate, and become 



Fig. 64. — Ripe spores and elaters oi A. Icezns, x6oo. 



more nearly oval (Fig. 65, A). These are the young stomata, 

 and exactly as in the vascular plants, each divides longitudinally 

 by a septum which later separates in the middle and forms the 

 pore surrounded by its two guard cells. The walls of the other 

 epidermal cells become much thickened and distinctly striated. 

 Each epidermal cell contains a single large chloroplast like that 

 in the cells of the gametophyte, and between the cells are well- 

 developed air-chambers communicating with the stomata, so that 

 there is here a typical assimilative system of tissues. 



About the base of the growing sporogonium is a thick 

 tubular sheath representing in part the calyptra of the other 

 Hepaticae, but involving, besides the archegonium venter, also 



1 Gottsche (2). - Leitgeb (7), vol. v. p. 27. 



