ACROGENS— COVERED SPORES. 



33 



I. Spores naked. Embryo a simple cell without differen- 

 tiation into parts ; 



II. Flowers (Oogonium and Antheri- 

 dium) microscopic and rudimentary; 



III. Foliage a thallus, or frond, without 

 siomata (breathing-places) ; 



IV. Growth peripheral ; tissue cellular ; 

 no true roots, stems, nor leaves. 



Flo. 26.— Germi- 

 nating spore of 

 Lichen {Met/ato- 

 epora affitiis), show- 



We have enough edible Fungi in the Uni- 

 ted States to keep the poorest families in de- . 

 licious food if they will take the trouble to '°B peripheral 

 gather the plants in the country, or grow them — growth, x. 

 as they may without cost — in the cities. See Fungi in Manual. 



LESSON VII. 



CLASS TI—ACKOGENS— COVERED SPORES. 



58-60. Liverworts. 61. Mosses. 62. Charas. 63, 64. Ferns. 65. 

 Tree-Perns. 66. Alternate Generation. 67. Scythian Lamb. 



58. Acrogens. Covered Spores. The Liver- 

 worts introduce us to the second and higher 

 class of Cryptogams. The female flower 

 is now called an Archegonium (14). It is 

 no longer naked in its receptacle, like the 

 spore of the Lichen (Fig. 27, p) ; 

 but its vesicle, or nucleus, is cov- 

 ered by a cellular sac which simu- 

 lates a pistil (Fig. 27, a). This soon 

 ruptures at top, to admit the anthero- 

 zoids. 



Fig. 27.-0. Arohegoninm rj,j^ archegonia are usually enclosed in a 



of liiwervfOTi (Marchanlia poly- ._ ,i t ■ -n, i 't_ • ^i. 



mmpha):a. Btyle-lilie process; wide-mouthed cup. Each archegonmm, atter 



!i, body of it containing tlie fertilization, develops into a spore - case 



nuclcns;c, separate fllaments; (snoranaium, plural sporangia) containing 



V, oogonium of Le<aiiora tar- \ J ^ ^ ,-i ' • ^ -j 



tarra (Lichen). many spores; the spores are intermixed 



c 



