( 32 ) 
should seem to refer it, unmistakably, to the colourless series, there is 
never entirely wanting some slight evidence of coloration; which be- 
comes marked in Nephroma and Sticta, and is at least observable in 
Erioderma. There seems however to be no doubt entertained by au- 
thors that in all these cases the spores differ in type from those of Solor- 
ina; and the same view is, with some hesitation, accepted in this place. 
The family, as we understand it, is, in fact, —to give a wider, but not 
perhaps too wide a sweep to an observation of Professor Schwendener 
upon Sfticta,—especially remarkable for the number and importance of 
the structural contrasts which find their reconciliation in it; and it is 
then the less surprising that a certain ambiguity of type must be admitted 
even in the spore-characters. But, however often it embarrass the sys- 
tematist, this exuberance of differentiation, — whether exhibited in the 
veins or cyphell@ which diversify the under side, or the elsewhere almost 
unexampled prolifications of the upper; in the two-fold nature of the 
gonidial cells; in the extraordinary modification of the apothecia in their 
relations to the thallus; in the spores, reaching, for the most part the 
higher and often the highest stages of the colourless trpe, and yet ob- 
scured more or less by what suggests the coloration of the other; and, 
no less, in the spermogones and sterigmas, so far as these are known ; — 
may well be allowed to indicate to him, not doubtfully, the position of 
the group, as the true centre of Parmeliaceous lichens. In his disposi- 
tion of 1821 (Vet. Ac. Handi.) Fries makes his Peltigera (equivalent to 
our Peltigerei, excluding Sticta) the summit of foliaceous lichens, as 
Usnea of fruticulose; and Mever (Extwichk. p. 335) who gives to Sticta 
the second place, accords to Peltigera (in the same sense in which Fries 
understood it) the first ;+ as does Nylander (Sy.) to Sticta. 
XIV.—STICTA (Schreb.) Delis., Fr. 
Delis. Hist. Stict. 1222, spp. excl. Fr. L. E. pp. 49, 348. Mont. Pl. Cell. 
in. Ann.; M. et V. d. Bosch Lich. Jav. p.8. Tul. Mém. pp. 20, 145, 
t. 1, f. 17-21, t. 2, f. 1-5. Norm. Con. p. 14, t. 1, f. 7, c,d. Mass. 
Mem. p. 27, t. 3-5. Koerb. Syst. p. 65. Th. Fr. Gen. p. 57. Mudd 
Man. Brit. Lich. p. 86. Stizenb. Beitr. lL. ¢. p.174.  Schwend. Un- 
tersuch. 1. ¢. 3, p. 166, t. 9, f. 2-7. Sticta max. p., et Parmelix spp., 
Ach. L. U. pp. 87-9; Syn. pp. 230,195. Parmelie spp., Wallr. Eschw. 
Bras. Scher. Spicil. Sticta et Ricasolia, De Not. Framm. Lich. p. 5. 
1“ Thallus. . . in Peltigereis foliaceus vix non perfectissimus evadit struc- 
* tura formaque. Eschw. Lich. Bras. 1. c. p. 171, where there seems to be no doubt 
that Vephroma (whether or not taken to be a member of the next following genus) 
Peltigera and Solorina were in view; Sticta being here relegated to Parmelia. 
In his earlier work (Syst. p. 24) this author had by no means a clear conception of 
Nephroma. 
