526 DR LAUDER LINDSAY ON NEW LICHENICOLOUS MICRO-FUNGI. 



to other lichenologists ; and I doubt not that, if they take the trouble to make 

 similar microscopico-botanical testings, they will meet with many marked 

 instances in which their own results will differ both from mine and from those 

 recorded by authors, like Nylander, who have given prominence in their works 

 to chemical reaction as a botanical character.* This arises from the circum- 

 stance, already mentioned, that the same species, under different circumstances, 

 yields different colour- results with the same reagent. The following list could 

 have been largely extended had I introduced quotations from similar records 

 relating to the contents of my own Herbarium or of that at Kew. Eut such 

 plenitude of illustration is, for present purposes at least, quite unnecessary. 

 Omitting all instances of J/z^-reaction with iodine, whether* distinct or faint, the 

 other results of iodine-testing may be roughly classified as follows: — 



I. No reaction. 



Thelopsis rubella, Nyl. Exs. 96. According to Nylander (Prod. 196), its hymenial 



gelatine becomes red. 

 Nepliromium cellulosum, Ach. Hermite Island, Cape Horn. According to Nylander 



(Syn. 318), hymenial gelatine becomes blue. 

 Uroeolaria aetinostoma, Schser. Exs. 573. 

 Strigula Babingtonii, Leight. Exs. 35. 

 Lec.idea sphceroides, Smrf., accompanying Opegrapha atra in ray copy of Leighton*s 



Exs. 245. According to Nylander (Scand. 204), hymenial gelatine gives in different 



forms of the plant various shades of violet, or wine-red. 

 L. f areolaris, Schser. Exs. 293. 



L. Ligldfootii, Ach. v. commutata, Schser. Exs. 581. Apothecia here degenerate. 

 Calicium turbinatmv, Schser. Exs. 6. 

 Verrucaria chlorotica, Ach., Nyl. Exs. 96. 

 V. elceina, Schser. Exs. 590. 



V. Uformis, Schan*. Exs. 109 (— V. ohlarotiea, Ach.) 

 V. laivata, Leight. Exs. 198. 



V. rupestris, accompanying V. pyrenophora in my copy of Leighton's Exs. 245. 

 Melaspilea arthonioides, Nyl. Exs. According to Nylander (Prod. 159), hymenial 



gelatine becomes wine-red or bluish. 



II. Reaction violet, red, or brown. 



Lecidea luteola, Leight. Exs. 150. Ilymenium deep violet, with reddish tinge. 



L. Waldenberglana, Ach., Leight. Exs. 123. Hymenium very faint purple. 



L. cupidaris, Ach., Leight. Exs. 122. Hymenial gelatine and asci deep brownish-red; 



hypothecium (only) blue. 

 L. abietina, Ach., Leight. Exs. 124. Same reactions as in L. cupularis. 

 L. lurida, Nyl. Exs. 131. Some tissues rose-red, others purple. Scha-r. Exs. 157, 



asci pale blue or wine-red; Hepp Exs. 121, asci wine-red. 

 L. exllis, Hepp Exs. 473. Asci violet. 



L. premnea, Ach. (saxicolous), Leight. Exs. 185. Asci lilac or lake-coloured. 

 L. atro-alba v. concentrica, Leight. Exs. 17. Hymenial gelatine violet. According to 



Nylander (Scand. 233), it becomes deep blue. 

 L. expanm, Nyl., Leight. Exs. 186. Hymenium indistinct blue, with a lilac tinge. 

 L. eoardata, Leight. Exs. 177. Asci faint blue; contained protoplasm orange-red. 



* The majority of lichenological systematists give no attention to cheniico-botanical characters, 

 e.g., Massalongo, Korber, Th. M. Fries and Mudd; while Nylander, on the contrary, gives them 

 decided prominence, e.g., in his " Lich. Scand." 



