LICHENS AND FUNGI OF OTAGO, NEW ZEALAND. 449 



more or less irregular in their surface, though generally with a defined roundish 

 form ; imraarginate ; epithalline (not hypophloeod). Sometimes all — sometimes only 

 the central perithecia — coalesce or become confluent— their apices only appearing 

 and remaining somewhat free and distinct — forming the projecting prominences, 

 which roughen the surface of the maculae. The spermogones are spherical, simple, 

 seated in the centre of the cluster of perithecia ; spermatia straight, linear, very 

 delicate, imbedded in hyaline mucilage. Pycnides have not been discovered. 



Its species form parasites affecting the thallus and apothecia of various of the 

 higher (foliaceous) lichens. The genus is variously regarded as a Fungus* and 

 Lichen, \ whether by Lichenologists or Fungologists. Those who regard it as a 

 Lichen class it usually among the Lecidece,\ though it appears to me, if it is to 

 be considered a Lichen, to have at least an equal affinity to certain genera of the 

 Graphidece and Verrucarice. 



Sp. 1. C. duhium (figs. 47 to 52). 



Parasitic on the thallus of various species of Sticta. 



1. On S.granulata, Bab. (sterile specimen), Signal Hill, Dunedin; Dr Sinclair. 

 The parasite affects generally the sterile, larger, and more granulose forms of the 

 thallus, and seems most abundant towards the ends of the lacinise. In what ap- 

 pears to be the young state of the plant, the perithecia are isolated and papillae- 

 form, with visible ostiola (figs. 47, 50 a) ; they gradually, however, become con- 

 fluent, forming difform groups (b) ; and lastly, maculaeform, exhibiting no distinct 

 ostiola. Both papillae and macula; vary greatly in size ; in both, the colour varies 

 from deep umber to black (in the dry state). Both are raised more or less above 

 the thalline surface ; both are only partly or apparently sub-immersed by their 

 bases. Interspersed among both occur much more minute, punctiform concep- 

 tacles, which may (when their normal contents are discovered) prove to be 

 spermogones or pycnides (figs. 47, 50 c). 



2. On S. fossulata Duf. (fructiferous and sterile specimens) ; corticolous (on 

 trees), Saddlehill Bush. 



In regard to site and external aspect, the parasite here has the characters de- 

 scribed in No. 1. It is abundant on some specimens of the Sticta towards the 

 tips of the lacinise, to which it sometimes gives, even to the naked eye, a black- 

 mottled appearance (fig. 49). There is the same transition from papillae to 

 macula; (figs. 51-2), the latter apparently being always due to the confluence of 

 the former. Here, however, the papillae are more irregular in form, and the 

 ostiole is never distinct. The maculae are generally more or less raised or convex 

 on their surface ; and they are sometimes regularly spherical (figs. 49, 51 a), in 

 which case they closely resemble the apothecia of certain Arthonice (e.g., A. lurida 

 Ach). More generally, from the coalescence of several maculae, or difform sori 



*Ntlander, Prod. 52. f Stizenberger, 163. \ lb. 163. 



