2 LINDSAYj ON POLYMORPHISM IN LICHENS. 



than to Fungi, which exhibit none of their other and more 

 usual forms of fructification, I can no longer, therefore, 

 hesitate in at least calling the attention of botanists to the 

 subject, in order that observation may be directed to the 

 groups of organs in question, with a view to the confirmation 

 or correction of my results as the issue may prove. 



It may be that, as Nylander suggests, the organs which I 

 refer to Lichens as multiple forms of Spermogonium or Pycni- 

 dium are to be assigned rather to Fungi. But if such assign- 

 ment is to be agreed to, it must be made on much stronger 

 grounds than those advanced by that individual, though 

 experienced, Lichenologist ; especially seeing that my obser- 

 vations appear to have been so far confirmed by those of 

 Fuisting in Germany* and Gibelli in Italyf — according to 

 Professor de Bary of Halle.J Until it is proved that the 

 subjects of my present remarks belong to Fungi, with which 

 I have never seen them connected, I prefer assigning them 

 to the lower Lichens, with which I have — sometimes re- 

 peatedly — found them associated, and in the same relative 

 position with the recognised Spermogonia and Pycnidia of 

 Lichens. 



The solution of the question is, however, beset with diffi- 

 culties : whereof the principal is probably the fact that the 

 Spermogonia or Pycnidia in question sometimes or frequently 

 occur by themselves, without association with sporidiiferous 

 apothecia or perithecia, whether of Lichens or Fungi. This 

 group of isolated secondary reproductive organs may be held 

 to be illustrated by the old pseudo-genera Pyrenothea and 

 Thrombium, which all Lichcnologists are agreed, I think, in 

 referring to Lichens as either Spermogonia or Pycnidia. 

 The subjects of my present remarks are indistinguishable in 

 any of their essential characters from these genera, and are, 

 I believe, quite as much entitled as they to be assigned to 

 Lichens. The puzzling group known to the older writers as 

 Pyrenothea contains, I believe, various forms both of Spermo- 

 gonium and Pjcnidium — sometimes referable to the same 

 species {e.g., Lecidea abietina), sometimes to different 

 species, especially of genera of the Verrucariacece, Lecideacece 

 and Graphidece (Ar'thonia and Opegrapha). Indeed, I re. 

 gard it as an illustrative group of the organs Avhich are thg 

 subject of this communication. It includes the folloAvin„ 



* Vide footnote, p. 9. 



t Vide footnote, pp. 7 and 9. 



X 'Ilandbucli derPliysiologiscbenBotanik,' by Prof. Hofmeiiter: Section 

 on "Morphologic und PLysiologie der Filze, IlecLten, und Myxoniyceten," 

 by Prof, de Bary : Leipzig, 1866, p. 276. 



