Morphologie und Teratologie. 139 



the rest of the wall becomes divided into a number of irregulär lobes 

 which curve backwards. 



Rebonlia liemisplierica (L.) Raddi. No endophytic Fungus was 

 found in the thallus. The male receptacle is disc- or crescent- 

 shaped and bears longitudinal rows of antheridia, the youngest being 

 nearest the anterior margin: the growing point of the thallus does 

 not occur just below and in front of the receptacle as described by 

 Leitgeb, but is used up in the formation of the latter. The male 

 receptacle must therefore be regarded as a branch bearing one or 

 two growing points on its anterior margin. The antherozoids are 

 explosively ejected, due to the swelling of the mucilaginous contents 

 of the cells of the receptacle, those of the antheridium wall and the 

 antherozoid mother cells 



The air Chambers borne on the female receptacle communicate 

 with the exterior by barrel-shaped pores. The large cells of the 

 lowest tier of the latter are capable of altering their form so as to 

 partially close the pore and, on plasmolysis by salt Solution, the opening 

 is greatly diminished in size. If fertilisation occurs in one of the 

 archegonia the growing point of the shoot is used up in the for- 

 mation of the stalk of the receptacle, but if none of the archegonia 

 are fertilised the apex of the branch resumes its growth leaving the 

 withered receptacle behind. The capsule wall is one cell in thick- 

 ness except at the top, where a lens-shaped mass ofi cells occurs 

 representing part of the archesporium and remaining sterile. 



Preissia conunutata Nees. The air Chambers are well developed, 

 the pores being of the Compound type. Each of the latter is sur- 

 rounded by four or five superposed tiers of cells, the lowest tier 

 consisting of four cells. In plants growing in a moist atmosphere 

 and exposed to light the aperture of the pore is circular; if kept 

 dry or in darkness it is reduced to four radiating slits. The midnb 

 is traversed by numerous long fibres with pointed ends, the walls 

 of which are of a dark colour and much thickened. Each is deve- 

 loped from a single cell which grows enormously in length and forces 

 its way between the surrounding cells. Their chief function is that 

 of conducting and storing water. 



The midrib possesses a w-eli developed mycorhizal zone, a thick 

 Strand of fungus-containing cells occurring on each side of the middle 

 line. Infection takes place through the rhizoids and the cells retain 

 their protoplasm and nuclei, the latter becoming enlarged. Vesicles 

 occur in the hyphae, filled with granulär contents in the autumn but 

 empty in the spring. 



The capsule wall consists of a single layer of cells except at 

 the base and apex. There is a well-developed apical cap consisting 

 of a lens-shaped mass of cells: attached to its inner surface there 

 are a few cells of varying length having spiral or annular markings. 



Monoclea Forsteri HooKer. The thallus contains large oil bodies 

 occurring in two cell layers, one immediately below the upper epi- 

 dermis and the other immediately above the lower epidermis. 

 On Solution in alcohol the bodies leave behind a proto- 

 plasmic envelope. No crystals occur in the living plant but after 

 preservation in alcohol they appear in almost every cell. They take 

 the form of special Clusters of radiating crystals, are soluble in hot 

 water and probably consist of inulin. A Mycorhiza is present in 

 the thicker median portion of the thallus. 



The growing point consists of a group of w^edge-shaped cells, 

 sunk in a deep notch and surrounded by large uniceilular mucillage 



