The Scottish Nattiraiist. 167 



paginatus; apothecia nigra subinnata, parva (lat. circ. 

 .3 mm.), plana, acute marginata, margine scepe flexuoso vel 

 undulato ; sporae 8nae incolores ellipsoideae simplices, " 

 .006-.009 X .004-.006 mm., paraphyses valde irregulares 

 et non distinctse, nigro-a,piculatce ; hypothecium fuscum 

 vel fusco-nigrum, crassiusculum. lodo gel. hym. vinose 

 riibens (praecedente coerulescentia obsoleta vel nulla) 

 Saxicola, Mull. 



K. added to the hymenium developes first a yellow colour, 

 and soon thereafter stellate groups of reddish acicular crystals. 

 The thecce, especially the immature, have, upwards, thick 

 pellucid walls. Only a few detached spores have been seen, and 

 none, it is believed, in a mature state. 



In August of 1876 I picked up a Lecidea near Salen in Mull, 

 whose characteristics may be given as under, and to which I 

 gave the name L. contortula. 



Thallus pallide cinerascens vel nonnihil plumbeo-cine- 

 rascens crassiusculus, rugosulus, rimoso-areolatus (K — 

 C — ); apothecia nigra adnata majuscula (latit. 1-2 mm.) 

 plana vel convexiuscula, crasse marginata, umbonata et 

 gyroso-plicata; sporse Sn^e incolores simplices, oblongaevel 

 fusiformi-oblongse, .015-.021 x .006-.0075 mm.; paraphyses 

 mediocres, satis bene distinctas, fusco-apiculatse ; hypothe- 

 cium fusco-nigrum supra fuscum. lodo gel. hym. 

 coerulescens dein vinose rubens praesertim thecse. 

 Saxicola. 



A comparison of this with the more recently discovered 

 Lecidece reveals a near affinity, if not identity, with L. subuni- 

 bonata i]^y\.) described in "Flora" 1876 p. 236. 



By the way, the distinction subumhonata had previously been 

 given to another Lecidea also described in Flora 1872, p. 358, 

 and ought, accordingly, to be changed ; but as I have no wish to 

 emulate the rather sharp practice which prevails pretty extensively 

 on the continent, I merely throw this out as a hint to those 

 more immediately concerned in the matter. To be sure the 

 two lichens indicated under the same name are rather closely 

 aUied, but according to modern ideas of specific distinction it is 

 scarcely likely that the two descriptions are meant for the same 

 lichen. 



The point concerning the Lecidea from Mull to which I wish 

 to draw attention is this : The application to the thalamium of 

 a solution of Iodine of the strength recommended is immediately 



