GLASGOW SOCIETY OF FIELD NATURALISTS. 91 



5_10-loculares, -018— "045 X -006— -008 mm.; paraphyses 

 crassse (ci'assit. -0025 — -0033 ram.), creberriter articulatse, iodo 

 flavescentes, apicibus fuscis clavatis ; bypothecium incolor. Sporse 

 iodo violacee tinctse. 



Ad cortices prope Montreal (Dr. M. Black). 



Forte nimium arete affinis Gr, inustse. (Ach.) 



Calidia rhizophora, gen. nov. 



Thallus pallide cinerascens tenuis farinaceus ; apotbecia adnata 

 fusca parva (latit. -2 — '4 mm.) plana vel convexiuscula, intus 

 obscura, albo-marginata, margine e fibrillis (latit. circiter "0035 

 mm.) irregularibus ramosis non-septa tis, omnino composito; sporse 

 Snse incoloi-es simplices vel 1 — S-septatse obovatse, utrove apice 

 attenuatse, -01 — -014 x "0035 — "0045 mm.; paraphyses valde 

 indistinctse, apicibus incoloribus non-clavatisjJhypotheciumfuscum 

 vel nigricanti-fuscum. Iodo gel. bym, ccerulescens prsesertim the- 

 carum, dein fulvescens. 



Ad cortices prope Funchal in Madeira, lecta a Joseph Payne. 



The thecse are not arthonioid,. but are (as well as the spores) 

 obovate and sharp-pointed at the lower end. The paraphyses are 

 rendered tolerably distinct by means of K. 



This lichen holds a somewhat anomalous position. On the one 

 hand it presents considerable affinity to a section of the Arthonise 

 in which A. subvarians (Nyl.) may be taken as the type, and on 

 the other, it plays between the Lecidese and Lecanorse, although 

 more nearly allied to the foi-mer. The hymenium is that of an 

 Arthonia (although firmer), but the thecse which constitute the 

 main element of distinction in this genus are not arthonioid ; and, 

 although the shape, &c., of the spores might lead us in the same 

 direction, yet there are similar instances amongst the Lecideae. 

 The structure of the margine which is extended beneath the apo. 

 thecia is, so far as my knowledge goes, unique, more especially as 

 it presents the same characters in old and young apothecia and 

 cannot, accordingly, be reckoned as a degeneration from a known 

 type. The gonidia are of average size, and often irregular in 

 outline. 



The specimen is small, comprising only 6 Apothecia, and I dare 

 not, meanwhile, make further investigations as to internal structure. 



