324 SYSTEMATIC 



fruits of Chiodecton (sect. Enterographci). The spores are elongate, narrow, 

 pluri-septate, and colourless or brownish, except in Darbishirella in which 

 they are ovoid, 2-septate and brown. 



The affinity of Dirinaceae and Roccellaceae with Graphidaceae was first 

 indicated by Reinke 1 and elaborated later by Darbishire 2 in his monograph 

 of Roccellaceae. The apothecia in some species of Dirina are ellipsoid rather 

 than round; in several genera of Roccellaceae they are distinctly lirellate, 

 and in Roccella itself some species have ellipsoid fruits. The fruticose thallus 

 is predominant in Roccellaceae, but its evolution from the crustaceous type 

 may be traced through Roccellina which is partly crustaceous and only 

 imperfectly fruticose. 



In most of the genera only one species is recorded. Roccella, represented 

 by twelve species, is well known for its dyeing properties, and has a wide 

 distribution. Like other Graphidineae they are mainly plants of warm 

 regions, many of them exclusively maritime rock-dwellers. 



The following synopsis of the genera is the one given by Darbishire in 

 his monograph. 



Cortex fastigate, of palisade hyphae. 

 Spores colourless. 



Hypothecium black-carbonaceous. 

 Apothecia round. 



Thallus fruticose i. Roccella DC. 



Thallus crustaceous-fruticose 2. *Roccellina Darbish. 



Apothecia lirellate 3. *Reinkella Darbish. 



Hypothecium colourless. 



Gonidia present under the hypothecium 4. *Pentagenella Darbish. 



Gonidia absent from hypothecium 5. *Combea De Not. 



Spores brown or brownish. 



Medulla of parallel somewhat loose hyphae 6. *Schizopelte Th. Fr. 



Medulla solid, black 7. *Simonyella Steiner. 



Cortex fibrous, of parallel hyphae. 

 Apothecia round. 



Hypothecium black-carbonaceous. 



Apothecia with thalline margin 8. *Dendrographa Darbish. 



Apothecia with proper margin 9. *Roccellaria Darbish. 



Hypothecium colourless 10. *Darbishirella A. Zahlbr. 



Apothecia lirellate n. *Ingaderia Darbish. 



SUBSERIES 3. CYCLOCARPINEAE 



This last subseries includes the remaining twenty-nine families of Asco- 

 lichens. They are very varied both in the fungal and the algal symbionts. 

 The fruit is more or less a discoid open apothecium. The gonidia belong to 

 different genera of Myxophyceae and Chlorophyceae, but the most frequent 

 are Protococcaceae. Families are based largely on thalline structure. 



* Reinke 1895. * Darbishire 1898. 



