306 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



curious condition. The tips of the fertile ramuli are curled 

 into a little spiral, which after a time consists of about three 

 articulations. All of these swell, but the second the most, 

 so as to appear to be supported at its base by the other two. 

 The integument becomes slightly rough, and at length strongly 

 granulated, like the spore of a Genea, and eventually, in some 

 cases, a second spore is added at the tip. The genus Zygo- 

 desmus deserves notice, from the peculiar character of its 

 threads. It is possible, indeed, that the species may be condi- 

 tions of certain Thelephoroid Fungi, but there is no evidence 

 to prove that this is the case. The mycelium, which is always 

 well developed, and creeps extensively, is remarkable for its 

 threads, being frequently very deeply constricted on one side 

 only, so as to look like an imperfect articulation (Fig. 68, g). 

 Several species occur in this country, and more than one in 

 South Carolina. I have never seen the mycelium of any well- 

 ascertained Thelephoroid present similar constrictions. 



325. Corda considers one or two of the genera of this tribe 

 as parasitic upon other moulds, and in consequence associated 

 them with such Fungi as Uredo, an association quite marvel- 

 lous in the hands of a person who had studied and accurately 

 figured so many Fungi. Sepedonium mycophilum, at least, 

 is very widely diffused, and, probably, accompanies the genus 

 Boletus everywhere. I have specimens from the Himalayas 

 and the Swan River. 



2. MucEDiNES, Ft. 



Mycelium generally abundant, giving off erect fertile threads, 

 on which the naked, mostly simple, spores are scattered, or 

 collected into little heads, sometimes forming simple or 

 branched moniliform threads. Fruit sometimes double, the 

 second fruit consisting of a large encysted spore of a perithe- 

 cium containing asci with sporidia, or a sporidiferous cyst. 



326. This division comprises a- great portion of those pro- 

 ductions which are known by the name of moulds, with the 

 exception of the true Mucors, which are separated from them 

 rather by structure than by external aspect. The species are, 

 for the most part, pure white, or assume bright and pure tints ; 

 a few only, as the common species of PolyacMs, which are 



