(93 ) 
to C. pulposum.—15. C. pulposum (Bernh.). Ontheearth. Including 
here a variety of forms, more or less clearly associable together, but the 
limits of which are uncertain. One of these, distinguishable by its 
commonly concave apothecia, the margin of which is more or less 
granulate-irregular, seems hardly diverse from C. crispum, Nyl. (Fellm. 
Lich. Arct.n.7) and has occurred in Canada (Mr. Drummond) Massa- 
chusetts (Mr. Willey) Vermont (Mr. Frost) and New York (Dr. Sartwell). 
— But, here at least, this lichen approaches very closely to another, — 
C. tenax (Sw.) Ach., especially notable for the marked development of 
the thallus; occurring, in calcareous soils, in Pennsylvania (Muhl.), Ohio 
(Lesquereux) and New York.—— And there is still another, ill-compara- 
ble with either of the two preceding, and differenced by the disappear- 
ance of the thallus, the attenuated margins of the rather large apothecia, 
and the more numerous longitudinal series of cells in the spores, which 
agrees so well both with the character and with Swedish specimens (Herb. 
Torssell) of C. imosum, Ach., Nyl., that it may perhaps be referred to 
it. It has been found as yet only on the prairie-lands of Ilinois (Mr. Hall). 
——16. C. melenum, Ach. On caleareous rocks. Greenland, J. Vahl. 
(Th. Fr. Lich. Aret. p. 277.)——17. C. cristatellum, Tuck. Lich. Calif. p. 
29. On the earth, in gravelly soils, New Mexico (Mr. Fendler). Califor- 
nia (Mr. Bolander).——18. C. furvum, Ach., Nyl. On calcareous rocks, 
New York, and Maryland. And the same, probably, from Vermont (Mr. 
Russell) and Canada East. With the aspect of C. flaccidum, and very 
near to it. Ihave seen but one fertile specimen (Trenton Falls) the 
ellipsoid, muriform spores of which agreed exactly with those of European 
specimens (Herb. Floerk. Herb. Fr.) and with the description of Nylander. 
——19. C. granosum (Wulf.) Scher. Ohio? <A single specimen, unfor- 
tunately infertile, of this well-marked lichen, occurred to me in the 
herbarium of Mr. Lesquereux, where it was associated with lichens of 
Ohio; and similar, also infertile specimens were found on rocks, in Illinois, 
by Mr. Hall. The plant is found in Europe on rocks, especially calca- 
reous; and very rarely also on trees. It is closely akin to C. furvum. 
20. C. pustulatum, Ach. On mosses; Pennsylvania (Mubl.). On calca- 
reous rocks; Alabama (Mr. Peters). Well-marked by the minute apothe- 
cia, and no less in habit. In the latter respect however it is not impossi- 
ble to detect some points of agreement, especially in the lobation, with 
states of the last. ——21. C. stenophyllum, Nyl. (North America, Drum- 
mond) is compared with C. pustulatum, with which it is described as 
agreeing in its ‘sufficiently small’ and concave apothecia; but is unknown 
to me. 
XXV.—LEPTOGIUM, Fr., Nyl. 
Leptogium, Fr. S. 0. V. p. 255. Nyl. Prodr. p. 24, max. p.; Syn. p. 118. 
max. p., t. 2, f. 6-7, t. 4, f. 10-17; Lich. Scand. p. 32, max. p. Colle- 
