IV. MAESILEACEJB. 



909 



M, salvatruc. Prothallus developed, 



bearing the avchegonium in the 



centre (mag.)< (Hanstein.) 



MarsUea sdlvairix. 



Sporangium, showing 



the antheridia. 



Marsilea salTiati'ix. 

 Sporangium, showing the 

 antheri£a and macrospores. 



M, salvatrix, Prothallus 



leaving the spore, about to 



enlarge. (Hanstein.) 



M. salvatrix. Gelatinous cylinder 



escaped from the sporocarp, laden 



with sporangia. 



contain, but on opposite sides, micro- and macro-spores {Ma/rsilea). Maoeo-spoeangia 

 {oophoridia) and miceo-spoeangia {antheridia) formed originally of cells, containing 

 a cellular mass, which afterwards divides into granules agglomerated in fours. The 

 antheridia give birth to fragile vermiform many-haired antherozoids, similar to those 

 of Ferns. In the macro-sporangia all the cells are absorbed with their 4 contained 

 granules, except one, in which one of the 4 granules is further developed into a 

 spore ; this spore, enveloped in a mucous layer, rapidly emits a prothallus, which 

 bears at its centre a large cell surmounted by a hollow papilla, formed of 4 rows of 

 superimposed cells ; this is the archegonium, on which the antherozoids act to pro 



duce fertilization. 



GENEEA, 



Marsilea. 



Pilularia. 



MardleacetB resemble Ferns in their coiled fronds, but the structure of their spores or reproductive 

 organs brings them nearer to LycopodiacecB. 



This family inhabits the temperate and hot re^ons of both worlds and of New Holland. It contains 

 but few species, of which however one (ilf. salvatrix) has of late acquired celebrity from having been 

 the means of saving the lives of a party of intrepid exploring naturalists, who, lost in the immense 

 deserts of Australia, had no other food but its sporangia, [These after the drying up of the pools in 

 which the Marsilea grows, are found in vast abundance on the surface of the soil, and contain a certain 

 proportion of starch and probably other nutritious matters.] 



