"5 



PLATE 7. 

 Calicium quercinum Pers. 



1. Plants natural size upon a section of bark. 



2. Apothecium and portion of stipe magnified. 



3. Section of apothecium. 



a, thecium ; b, hypothecium ; c, hypbal tissue continuous with the 

 hyphae of the stipe. 



4. Vertical section of thallus. 



a, upper protecting layer ; b, algal layer ; c, medullary layer ; d r 

 rhizoidal hyphae. 



5. Dissolving spore-sac, spores and paraphyses. 



6. Spores. 



a, immature ; b, mature. 



4. Cyphelium Ach. Vet. Ac. Handl. 1814 : 215. 1814. 



Some authors, including Tuckerman, combine this genus with 

 Calicium, but the spore-characters are, however, so well marked that 

 I have decided to maintain it. In general, the representatives 

 of the genus indicate a higher development than is met with among 

 the Calicia. In the higher forms the thallus is very distinct, becom- 

 ing even faintly areolate in species in which the stipe is shortened 

 (C. sessile). Sometimes this shortening of the stipe is more appa- 

 rent than real, that is, it becomes partially hidden by the thallus as in 

 the European C. corallinum in which the thallus is quite thick. The 

 general anatomical characters of this genus are the same as in Cal- 

 icium quercinum (see Plate 7). 



The habitat and distribution of the Cyphelia are about the same 

 as that of the Calicia. As far as I have been able to observe, they 

 are perhaps more restricted to the eastern states. The number of 

 species occurring in the territory will perhaps not exceed six or 

 seven. As already stated, the lower forms of this genus have been 

 included in the genus Mycocalicium. Sphinctrina proper has not 

 come to my notice from the territory. S. tubaeforme Mass. and S. 

 Anglica Nyl. are doubtless species of Cyphelium. 



For the general morphology of this genus see Plate 8. For the 

 spore-characters see Plate 15, Fig. 1. 



5. Acolium Ach. Lich. Univ. 232. 1810. 

 In many respects this genus is essentially different from the pre- 

 ceding. The stipe is very much shortened, especially in the only 



