10 R. H. Howe: MANUAL OF THE GENUS USNEA 
Diacnosis: Zhallus pendulous, primary branches articulate and 
inflated. 
DESCRIPTION — typical: Z7ha//us pendulous, catenate, terete or 
compressed, virescent to tawny, cortex nitidous or glabrous (sec- 
ondary branches and fibrils now papillo-sorediate); primary 
branches deformed, articulate, internodes inflated (max. diameter 5 
mm.), foveolate, dichotomous, glabrous (max. length 30 cm.) ; 
secondary branches subdichotomous, much divided, scabrous ; 
fibrils capillaceous, tortuous. Apothecia rare, subterminal, small 
(max. diameter 5 mm.), disk pruinose, flesh-colored or buff, periph- 
ery ciliate. Spores 8-10 x 5-Op. 
CONTINGENT PHASES: Unobserved. 
SUBSTRATA: Trees, for the most part deciduous. 
GEOGRAPHICAL DISTRIBUTION: Reported by Tuckerman as 
‘‘ill-exhibited in North America; but it is not wholly wanting on 
the Pacific Coast ; Scouler ; Macoun.’ Professor Macoun reports 
it (Cat. Can. Pl. '7: 61. 1902) from [Hastings] Burrard Inlet, 
British Columbia, Canada (1889),* and also from Victoria, Van- 
couver, British Columbia, Canada (1875). The Victoria record is 
the one to which Tuckerman referred; the specimen is now in the 
Museum at Kew, England (fide Macoun). Professor Bruce Fink 
in ‘‘ Contributions to the Lichens of Minnesota— VII” (Minne- 
sota Bot. Stud. 3: 194. 1903) records three specimens (vos. 143, 
711, 1636, herb. Univ. Minn.) collected respectively at Beaudette, 
Emo, and Harding in 1901. These specimens, which Professor 
Fink writes me he was already aware were wrongly determined, 
have been kindly sent me by Dr. C. O. Rosendahl of the Univer- 
sity of Minnesota and prove to be typical Usnea cavernosa Tuck. 
Professor Macoun has sent me a sterile specimen, collected 
Aug. 16, 1909, at Ucluelet Arm, north of Barclay Sound, British 
Columbia, which, though no doubt closely approaching this 
species and to be referred only here, is, nevertheless, decidedly 
atypical. Itis only slightly inflated, decidedly papillate, not foveo- 
late, and has non-capillaceous fibrils. It certainly ill exhibits 
true Usnea articulata. 
The inclusion of this species as a North American plant is 
only empirical. 
* This specimen (no. 10), kindly sent me by Professor Macoun, is A/ectoria och- 
+oleuca sarmentosa Nyl. 
