440 DR LAUDER LINDSAY ON THE 



plentifully on the branches and trunks of old or dead trees in Greenisland 

 Bush. 



In site and in general characters, this species resembles M. perrugosaria, 

 from which, however, it differs in the character of its spores. The perithecia are 

 black and papillseform ; the upper half seated on the epithecium, generally of old 

 deformed apothecia, the lower immersed in its tissues ; generally isolated or 

 discrete ; scattered in considerable numbers on a single apothecium (fig. 31). 

 Like those of M. perrugosaria, they have externally the characters of a minute 

 Verrucaria. No thecae were seen, but the perithecia contained abundance of brown, 

 round spores, about -00015" to -00025" in diameter; simple, or with double 

 contour (fig. 34). They cannot be confounded with the spores of the Parmelia, 

 which are greatly larger, -00045" long, -0003" broad ; colourless ; and oblong or 

 oval ; though they are also simple, with or without a double contour, according 

 to age (fig. 35). The beautiful blue reaction with iodine of the thecse and hy- 

 menial gelatine of the Parmelia further sufficiently distinguish it from the 

 hymenium of the parasite. Nor can the Microthelia be confounded with the 

 parasitic Abrotliallus Curreyi* which affects the thallus of the same Parmelia, 

 and which may in some of its conditions or parts be mistaken for the spermogones 

 of the Parmelia. The Abrotliallus is distinguished as a Lichen by the blue re- 

 action of its thecse and hymenial gelatine with tincture of iodine, and by the pre- 

 sence of distinct paraphyses with very granular and dark brown tuberculated 

 heads, as well as by its general analogies. 



Materials scarcely exist for the accurate determination or full description 

 of M. Cargilliana, whose name is in honour of my friend John Caegill, F.R.G.S., 

 of Greenisland, Member of the Legislative Assembly of New Zealand, and one of 

 the best known pioneer settlers of Otago, to whom I was indebted for many acts 

 of kindness in the course of my Otago excursions. 



Sp. 3. M. Hamalinaria, nov. sp. (figs. 44-6). 



Parasitic on the thallus of Ramalina calicaris, Fr., as it grows on the branches 

 of trees (especially dead " Goai") in Greenisland Bush. 



It occurs as extremely minute (microscopic), black, punctiform perithecia, 

 scattered in great numbers, and in a state of close aggregation, over the surface 

 of some of the branchlets, to which they give a dirty or blackish aspect (fig. 44). 

 They are distinct only under the lens. Their wall consists of closely aggregated, 

 dark brown, very small cells (fig. 46) ; but they contained no spores ; and my pre- 

 sent materials are, therefore, imperfect for full description or accurate determina- 

 tion. It appears, however, to be the same parasite, which occurs occasionally 

 in this country on R. scopulorum, Ach. (Linds. Mem. Sperm, p. 130), and which I 



* Described in the Section on Lichens, p. 409. 



