220 MORPHOLOG K 



like an earth star (Scleronjasterl, or portions of the surface become gelatin- 

 ized (Phallogaster). The last-named one grows on very rotten wood, whilt 

 most of the others grow on the ground. 



470. Order Lycoperdales (Lycoperdinese), — These include the "puiJ- 

 balls," or "devil's snuff-box" (Lycoperdon), and the earth stars (Geaster). 

 The basidia form a distinct hymenium, but at maturity the entire inner por- 

 tion of the plant (except certain peculiar threads, the capillitium) disinte- 

 grates and with the spores foriris a powdery mass. 



471. Order Nidulariales (Nidulariineae). — These are known as bird-nest 

 fungi. The fruit Ijodv when mature is cup-shaped, or goblet-shaped, and 

 contains minute llattened circular bodies fperidiola) containing the spores. 

 The intermediate portions of the fruit body disintegrate and set the peri- 

 diola free, which then lie in the cup-shaped base like eggs in a nest. 



472. Order Plectobasidiales (Plectobasidiinese). — The basidia do not 

 form a definite hymenium, but are interwoven with the threads inside, or 

 are collected into knot-like groups. (Examples: Calostoma, Tulostoma, 

 Astr;rus, Sphsi-robolus, etc.) 



472a. Lichens. — -The ]>lant body of the lichens (see paragraphs 200. 

 201) consists of two component parts, the one a fungus, the other an alga. 

 The fructification is that of the fungus. The fruit borlv shows the lichens 

 to be related somu to the Ascomvcetes, others to the Ihmenomycetes, and 

 Clasteromvcetes. The}^ are usually classified as a distinct class or order 

 from the fungi, but a natural arrangement would distribute theiu in sev- 

 end of the orders above. Their special relationship with these orders has 

 not been satisfactorily worked out. For the present they are arranged as 

 follows: 

 Ascolichenes. 



Pyrcnocarpoiis lichens (those wilh a fruit body like the Pyrenomycetes). 



Gvmuociirpous lichens flhose with a fruit l.iodv like the Disconivcetes). 

 Hymenolichenes (Uiose with a fruit body like the Ilymenomycetes). 

 Gasterolichenes (those with a fruit body like the Oasteromycetes). 



From a vegelative slandj.ioint there are two types according to the dis- 

 tribution of the elements. 



1st. A\'here the fungal and algal elements are evenly distributed in the 

 plant bod)' the li(hen is said to be honmiinncroiis. There are two ty]>es of 

 these: 



(/. Fi/iiDicntciis licJ/cjis, examjile, Kphrbe pubescens. 



/'. GeJiiliuoiis l/cheiis, example, Collema (with the alga nostiic"), Pln'sma 

 ("with the Chrooc(Kcacea'). 



2d. "Where the elements arc stratified, as in Fannelia, etc., the lichen is 

 sai'l to be liefcnnncroiis. In these there are three l\'prs: 



(7. Cm siliceous lichens, the i)lant body is in the form of a thin incnista 

 lion on rocks, etc. 



