260 INTRODUCTION TO BOTANY 
that a single plant (Polyporus squamosus) may produce as 
many as 11,000,000 spores. The same authority states that 
one “shaggy mane” (Coprinus cunatus) mushroom may pro- 
duce 5,000,000,000 spores. It is obvious that only a small 
number of these spores succeed in producing new plants; 
otherwise they would very soon occupy the earth. 
246. Puffballs. One of-the most important differences be- 
tween puffballs (fig. 202) and mushrooms is that puffballs 
produce their spores within an inclosed reproductive body 
instead of upon gills or within pores. Puffballs may become 
quite large, even a foot in diameter, and, when ripe, may con- 
tinue to emit small clouds of spores intermittently for several 
years. One giant puffball (Lycoperdon giganteum) was esti- 
mated ! to contain 7,000,000,000,000 spores. 
247. Classification of the thallophytes. The following is the 
classification of the thallophytes, including the chief genera 
that we have considered. This classification is placed here for 
use as a general summary, and not primarily to be committed 
to memory. If studied carefully, it will give a good review 
of the three chapters on the groups of thallophytes. 
Group A. THALLOPHYTES. Since the bacteria and the blue-green alge 
are so much alike in structure and in methods of reproduction, they are 
classified together rather than with the fungi and alge respectively. 
Crass J. ScuizopnyTes (the fission plants) 
Sus-ciass I. Scuizomyceres (bacteria, or fission fungi). Ilus- 
trated by numerous type forms and various methods of living 
Sur-ciass I]. Scurzopnyces, or Cyanophycez (the blue-green 
algze, or the fission alge). Leading genera used as illustrations 
— Nostoc, Oscillatoria 
Crass IT. ALG 
Sus-ciass I. CuLoropuycr.® (the green alge). Leading genera 
used as illustrations — Pleurococcus, Spirogyra, Cladophora, 
Vaucheria, Chara 
Sus-ciass IL Prvornycer.x (the brown alge). Leading genera 
used as illustrations — Fucus, Sargassum 
Sup-crass IIT. Ruopornycea (the red alge). Leading genus 
used as illustration — Dasya 
} Buller, A. H. R., Researches on Fungi. Longmans, Green & Co., 1909. 
