76 Transactio'iis . — Bo tait // . 



Parmelia obversa, Strn. 



Thallus flavescens vel ochroleucus, aclpressus, parvus, 

 rugosus vel potius corrugatulus, inargine laciniatus et crenu- 

 latus, subtus niger vel nigricans, parce nigro-fibrillosus ; 

 apothecia fusco-rufa, parviuscula, margine thallino, integro, 

 saepe inflexo cincta ; sporae 8, variantes, oblongae vel oblongo- 

 ellipsoidiB, 0-013-0-02 x 0006-0-008 mm. Spermogonia fere 

 integre nigra, spermatia cylindrica vel exacte cylinclrica, recta, 

 0-006-0-009 X circ. 0-0007 mm. Ad cortices et praesertim 

 ad lignum decorticatum. Tballus supra K flavens ; medulla 

 albaK-C-. 



In the various collections of lichens from Australia there 

 are several ParmclicB growing on charred wood, which have 

 very curious and constant chemical reactions on the white 

 medulla. Unfortunately, all the specimens are barren. I can- 

 not, however, pass them over on this account. 



Parmelia exoriens, Strn. 



Thallus pallidus vel luteseenti-pallidus, rugulosus, mem- 

 branaceus, laciniatus, laciniis margine crenatis et sorediosis, 

 subtus pallidus vel hinc inde nigricans, parce radiculo- 

 sus ; medulla alba crassiuscula, K obsolete violaceus dein. 

 C addito, leviter sed distincte rubro-purpurascens vel magenta. 

 Sterilis. Ad lignum carbonizatum, prope Brisbane {F. M. 

 Bailey) et in New South Wales {Kirton). 



The reaction by C, especially after the application of K, is 

 constant, and may be called a famt but decided reddish- 

 purple, or of the colour of magenta. These reactions resemble 

 those on the medulla of P. caperata, but there is, in addition, 

 the reaction by K, which on caperata is negative, w^hile the 

 after reaction by C on the same is a faint pink colour. 



Parmelia redacta, Strn. 



Similis praecedenti sed thallo magis adpresso, pallido vel 

 albido et caesio-soredioso. Illawarra, New South Wales 

 (EirtoJi). 



Parmelia hypoxantha, Strn. 



Thallus pallide ochroleucus vel etiam pallidus (K flavens) 

 saepe orbicularis, rnediocris, rugosus, laciniatus laciniis parvis, 

 imbricatis, margine crenulatis et sinuoso-lobatis, subtus niger, 

 parce et breviter nigro-radiculosus ; medulla alba (K — C — ) ; 

 apothecia fusca (latit. 2-5 mm.), plana, margine saepius crenu- 

 lato ; sporae 8, mcolores, simplices, late ellipsoidejfi, 0-009- 

 0.012 X 0-007-0-009 mm. ; hypothecium incolor. Corticola, 

 prope Warwick, Queensland {C. J. Gicythcr). 



The lower surface of the medulla (exposed after the black 

 hypothallus is peeled off) is almost always seen yellow or 



