CCENOGONIEL CCENOGONIUM. 257 



Fain. 2. CCENOGONIEI. 

 Thallus horizontal : eonfervoid-filamentous. 



The Pannariei, with all that the ultimate structure of the 

 family associates with it, are here regarded as au unavoidable 

 intercalation in the series of lichens which beginning with Usneei 

 finds its completion in Lecanorei (Gen. Llch. p. 150) and Ccenog- 

 onium as conceivably filling a similar place in Lecideacei. Leci- 

 deine elements are indeed far from unknown in the very various 

 differentiation of the Pannariei, etc. ; and Coenogonium found a 

 place in this Parmeliaceous neighbourhood, with Montagne, as 

 formerly with Fries. The same elements occur also in Gyalecta, 

 the first section of which (as here taken) is so well comparable 

 in the fruit with the genus now before us that when, in Cuban 

 specimens, the two plants are found growing together, it might, 

 without examination, be readily supposed that the apothecia of 

 Gyalecta lutea, wandering over some Confervaceous plant, thus 

 constituted Camogonium ; and Nylander places the latter next 

 before Gyalecta. It is not easy to follow him in reducing Gyal- 

 ecta to Lecidea; but perhaps nothing better now offers than to 

 regard Cwnogomum as Lecideaceous. 



XLIII. CCENOGONIUM, Ehrenb. 



Apothecia patellseforrn, pale. Spores (in narrowed 

 thekes) fusiform-ellipsoid, simple and bilocular, colourless. 

 Spermogones globular; spermatia fusiform, on simple ste- 

 rigrnas. Thallus composed of jointed filaments, loosely in- 

 tertangled, forming a more or less determinate, and rounded 

 web ; each filament consisting of 1, a central row of larger, 

 cylindrical cells with greenish content, taken to represent 

 gouidia; and 2, of slender thread-cells resembling and 

 answering to the ordinary lichen-filaments, which longitudi- 

 nally band, or loosely surround the first. , 



The principal authority for this type is Nylander, Obs. sur 

 les Ccenog. in Ann. Sci. Nat. 4, 16. p. 89, t. 12. Schwendener 

 Untersuch in Naeg. Beitr. 4, p. 172, t. 23, f. 18-21, should also be 



consulted ; and a note by Miiller in Flora, 1881, p. 235. The 



species belong all of them to the warmer regions of the earth. 



