192 REPRODUCTION 



also identified the plant, Lecidea irregularis, first described by F^e\ as also 

 synonymous with the fungus. 



Another name Orthidium was proposed by Muller=' for a type of fructi- 

 fication he found in Brazil which he contrasts or associates with Campylidium. 

 It has an open marginate disc with sporophores bearing acrogenous spores. 

 He found it growing in connection with a thin lichen thallus on leaves and 

 considered it to be a form of lichen reproduction. Po.ssibly Orthidium is 

 also a Cyphella. 



III. SPERMOGONIA OR PYCNIDIA 



A. Historical Account of Spermogonia 



The name spermogonium was given by Tulasne* to the " punctiform 

 conceptacles " that are so plentifully produced on many lichen thalli, on the 

 assumption that they were the male organs of the plant, and that the spore-, 

 like bodies borne in them were non-motile male cells or spermatia. 



The first record of their association with lichens was made by Dillenius'', 

 who indicates the presence of black tubercles on the thallus of Physcia 

 ciliaris. He figures them also on several species of Cladonia, on Ramalina 

 and on Dermatocarpon, but without any suggestion as to their function, 

 Hed wig's' study of the reproductive organs of the Linnaean Cryptogams 

 included lichens. He examined Physcia ciliaris, a species that not only is 

 quite common but is generally found in a fruiting condition and with very 

 prominent spermogonia, and has been therefore a favourite lichen for purposes 

 of examination and study. Hedwig describes and figures not only the apo- 

 thecia but also those other bodies which he designates as "punctula mascula," 

 or again as " puncta floris masculi." In his later work he gives a drawing 

 of Lichen {Gyrophora) proboscideus, with two of the spermogonia in section. 



Acharius* included them among the lichen structures which he called 

 "cephalodia": he described them as very minute tubercles rising up from 

 the substance of the thallus and projecting somewhat above it. He also 

 figures a section through two "' cephalodia " of Physcia ciliaris. Fries' looked 

 on them as being mostly " anamorphoses of apothecia, the presence of 

 abortive fruits transforming the angiocarpous lichen to the appearance of a 

 gymnocarpous form." Wallroth* assigned the small black fruits to the com- 

 prehensive fungus genus Sphaeria or classified lichens bearing spermogonia 

 only as distinct genera and species (Pyrenothea and Thrombium). Later 

 students of lichens — Schaerer^, Flotow", and others — accepted Wallroth's 

 interpretation of their relation to the thallus, or they ignored them altogether 

 in their descriptions of species. 



1 Fee 1873. 2 Muller 1890. ^ jujasne 1851. ^ Dillenius 1741. ^ Hedwig 1784 and 1789. 

 « Acharius 1810. ? prjes 1831. ^ Wailroth 1825. ^ Schaerer.1823-1842. ^0 Flotow 1850. 



