OF ARTS AND SCIENCES. 167 



— The larger form just named is not, however, confined to the north, 

 and exhibits in the tropics a peculiar luxuriance in quadrilocular spores 

 (v. Esclnceileri, Mihi ; given in Wright Lick. Cub. n. 94, iu part) 

 which renders necessary a modification of the genus-character, though 

 the liciien in question (like Physcia obscurascens, Nyl. Syti., as com- 

 jjared with Phijscia obscara) have little claim to be reckoned a species. 

 And, lastly, it may be said that Pyxine coccinen, M. & V. d. B. [Lic/i. 

 Jav. p. 40), which is distinguished, like the last variety, from the var, 

 sorediata by rather larger and quadrilocular spores, seems scarcely 

 otherwise to differ from this, but as P. picta, v. erythrocardia, from 

 the type of that species, or, as Physcia obscura, v. endochrysea, Ham p. 

 (the oldest name of a repeatedly named anamorphous condition) when 

 the medullary layer has become red from the same when as yet it is 

 only yellow. Systematic iXatural History is so much a matter of opin- 

 ion, that it may sometimes seem difficult, at this day, to fully assert its 

 position in the face of more purely objective science : surely, then, all 

 those who love the study of the system will desire that the term 

 " species " should express something worth knowing ; that its value 

 should be enforced and extended rather than diminished and frittered 

 away. 



U-MBiLiCARiA Caroliniana, sp. nov.: thallo membranaceo Isevigato 

 papuloso rotundato-lobato mox polyphyllo complicatoque olivaceo-fusco, 

 subtus lacunoso papillato-granulato atro, fibrillis paucis hinc inde ob- 

 sito ; apotheciis subelevatis mox plicatis deinque papillato-ijroliferis. 

 Sporte (2""^?) ellipsoidea3, muriformi- multiloculares, fuscfe, longit. 

 0,()30-iO'"™-, crassit. 0,020-23"""-. — U. mammulata, Tuckerm. Syn.N.E, 

 p. 69, non A(A\.Jide Nyl. /. infra cit. — Rocks, Grandfather Mountain, 

 N. Carolina, M. A. Curtis. High mountains of N. Carolina, S. B. 

 BucMey. A well-marked Umbilicaria, but the material before me for 

 its illustration is small. The plant was pretty confidently referred, at 

 the place cited above, to the North American Gyrophora -mammulata, 

 Ach. Syn., both from the diagnosis and the name ; and this judgment 

 seemed to be confirmed by my notes (made in 1850) on a specimen then 

 preserved in the museum of the Royal Society of Upsal. But Dr. Ny- 

 lander {Lich. Scand. p. 115) says distinctly, that Acharius's lichen is 

 " spodochroa, apotheciis non rite evolutis." Dr. T. H. Fries also refers 

 it {Lich. Scand. p. 154) to '■'■ spodoch-oa, rhizinis erohitis vel {maxi- 

 mam partem) in tubercula nigra ryiutafis ; " and it is evident that neither 

 of these references is to the North Carolina plant. U. dictyiza, Nyl. 

 {Flora Itatisb. 1869, p. 388) of the same section of the genus as the 

 lichen above described, is, according to Stizenberger {Index Lich. Hy- 



