DIl. LAUDER LINDSAY ON AKXHONIA MELASPERMELLA. 285 



5. Presence of distinct Paraphyses ivith clavate or Jcnoh-like, fre- 

 quently coloured, heads. Though these are characteristic of the 

 higher or typical Lichens, they do not occur, at least in this 

 form, in the lower. In them the paraphyses are visible either as 

 a confused mass of very delicate, filiform, hyaline tubes, or as a 

 mere striated jelly ; or they are altogether absent. In certain 

 genera, e. g. Verrticaria, these indistinct or obscure forms occur ; or 

 the paraphyses are absent, as they are also in Myriangium and 



En do 



carpon 



6. Presence of Spermogones. Spermogones and pycnides, how- 

 ever, even in the same species, are common ^to certain Fungi with 

 certain Lichens. They occur, for instance, in SpJiceria epicymatia^ 

 Wallr. (Fungi), which, moreover, is a parasite occurring on the 

 apothecia of a Lichen, Lecanora sitlfusca^ Ach., var. albella, Nyl. 

 in the genus Strigula (Lichens), and in certain species oiArthonia 

 and OpegrapJia f. In some cases, only spermogones or pycnides 

 occur with the sporiferous apothecia or pcrithecia, as in certain 

 species of AbrotJiallus Xy Peltigera, Lic1iina\ at other times the 

 spermogones or pycnides occur alone, or on a separate thallus 

 from the said apothecia or perithecia ; in some of which cases, at 

 least, the plants are truly dioecious. "We are yet, however, in 

 comparative ignorance of the proper line of separation (if such a 

 line actually exists) between pycnides and spermogones^ and of 

 the roles which they respectively play in the function of repro- 

 duction in either Lichens or Fungi. 



All which foregoing considerations lead me to the conclusion 

 that 



1- Arthonia melaspermeUa^ Nyl., has an equal claim to be con- 

 sidered, on the one hand, a Lecidea (Lichen), and a Patella?na 

 (Fungus). 



2. Certain dubious Lichens with a Fungoid facies, and Fungi 

 with a Lichenoid aspect, deserve and require re-examination and 



logists and lichenologists. 



yffi 



* Prodroiu. p. 85. 



^cidi 



y^tum, and others] the occurrence of spermogones has been well pointed out by 

 Unger, De Bary, and Tulasne (Cooke, 'Microscopic Fungi,' 1865, pp. 22, 31) ; 

 while the presence of pycnides, and the part they possibly play in the multi- 

 form fructification of Fungi, is adverted to by Berkeley in his ' Introduction 

 to Cryptogamic Botany,* 1857, p. 331, and ' Brit. Fungology,* p. 50. 



Memoir on the Sperm o 



gone, and Pycnides of Lichens,* oh ciL 



