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southern range; and the recent additions to our North American Flora 
have been almost wholly southern. P. speciosa passes with us also, as 
within the tropics, into its ascendant forms (v. podocarpa; v. galactophylla) 
and the last becomes also elongated (v. lewcomela, Eschw.) but has not yet 
been found in the extremest, decumbent state.——In like manner P. stel- 
laris, though its centre is not so clearly tropical as that of the last men- 
tioned species (P. speciosa, v. hypoleuca, Ach.) yet reappears, if I am not 
mistaken, in the warmer regions of the earth, in many elegant forms; of 
which two,—the var. astroidea, especially as characterized and diversi- 
fied in the form obsessa (Parm. obsessa, Mont.) and the var. Domingensis 
(Parm. Domingensis, Mont., Ph. crispa, Nyl.) are found from Carolina 
to the Gulf of Mexico; and the former extends also northward.—— 
P. picta (Sw.) Nyl. (Parmelia applanata, Fée) is a very distinct, tropical 
species, occurring throughout the country south of Carolina, and especially 
interesting on account of its general resemblance to the next genus; 
which in one of its species even simulates the apothecia of the Physcia. 
XII. PYXINE, Fr. 
Fr. 8. 0. V. p. 267. Mont. Pl. Cell. Cuba, p. 187. Nyl. Lich. exot. in 
Ann. Sci. Nat. 4, 11, p. 255, not.; Syn. Lich. N. Caled. p. 20. Tuck- 
erm. Obs. Lich. 1. ¢. 4, p. 400. Stizenb. Beitr. 1. c. p. 157. Lecidex 
spp., Ach. L. U. p. 216; Syn. p. 54. Circinarie spp. Fée Ess. p. 127, 
Lecidea sect. Pyxine, Eschw. Bras. p. 245, 256. Parmelia sect. 
Pyxine, Tuckerm. Syn. N. Eng. p. 35. 
Apothecia sub-scutelleformia, mox nigricantia. Spore oblongo- 
ellipsoideze, biloculares, fuscee. Spermatia oblonga; sterigmatibus 
pauci-articulatis. Thallus foliaceus, imbricatim lineari-laciniatus, 
subcartilagineus. 
With a thallus and spermogones comparable in most respects with 
those of Physcia picta, itself extraordinarily differenced by its black hy- 
pothecium, we have in Pyxine (which thus anticipates in the present, the 
immediately succeeding family) the Parmeliaceous apothecium trans- 
formed into what is, to.all appearance, the Lecideine; even the modifica- 
tions of this altered state repeating those of Lecidea. The development 
of the young fruit is however strictly Parmelieine; and, carefully ob- 
served, this fruit is seen also, even in P. Cocoes, to be sometimes pale, or 
even white (Tuckerm. Syn. N. Eng. p. 24) at the base. And in P. Meiss- 
neri (Obs. Lich. 1. ¢. 4, p. 400) the dealbation (for it is the denigration 
which is typical here) extends finally to the whole exciple; then undis- 
tinguishable from that of Physcia. 
The few known species are most closely akin, and confined to the 
warmer regions of the earth, excepting only P. Cocoes v. sorediata (Obs. 
Lich., 1c. Pyxine sorediata, Fr.) which, hardly distinguishable, in the 
