1903 | Collins,— Notes on Algae 207 
Alg. Austr. Exsicc, No. 274; Phyc. Austr., Pl. CCXLIV, 1862; J. G. 
Agardh, Sp. Alg., Vol. III, p. 495. 1876, = Heterodoxia denticulata J. Ag., Sp. 
Alg., Vol. III, part 3, p. 131, 1898. Not. D. denticulata J. G. Agardh Ana- 
lecta Algologica, Cont. II, p. 66, 1894, = Hypoglossum denticulatum J. Ag. 
Sp. Alg., Vol. III, part 3, p. 188, 1898, not of Kützing. D. Baerr? e spinu- 
losa Ruprecht, Tange des Ochotskischen Meeres, p. 244, 1856. Hypoglossum 
denticulatum Kützing, Tab. Phyc., Vol. XVI, p. 6, Pl. XLV, not Æ. denticu- 
latum J. Ag. Sp. Alg., Vol. IIl, part 3, p. 188, 1898. D. spinulosa (Rupr.) 
J. G. Agardh, Sp. Alg., Vol. III, p. 483, 1876. D. Moutagnet Kjellman, Algae 
of the Arctic Sea, p. 135, 1883. Farlow, Proc. Amer. Acad., Vol. XXI, p. 
471, 1886. Not D. Montagueana J. G. Agardh, Sp. Alg., Vol. III, part 1, 
p. 492, 1876, = Apoglossum Montagneanum J. G. Agardh, Sp. Alg., Vol. III, 
part 3, p. 194, 1898. D. Montagne: a typica Rosenvinge, Grénlands Haval- 
ger, p. 902, 1893. Pteridium spinulosum J. G. Agardh, Sp. Alg., Vol. II, 
part 3, p. 225, 1898, in part. 
The species seems to be common from Maine to Greenland, but 
at the southern limit to approach the narrower forms of D. alata. 
Some specimens from Gloucester are hard to assign. It would seem, 
however, that the true D. alata does occur on the New England 
coast; as for instance No. 140 of Farlow, Anderson and Eaton, Alg. 
Am. Bor. Exsicc. 
At Gloucester occurs, though apparently quite rare, D. angustis- 
sima Griff., which must be carefully distinguished from the narrow- 
est forms of D. alata. A single specimen, from Cape Ann, seems to 
be 2. denticulata var. angustifolia (Lyng.), agreeing well with speci- 
mens from Greenland named D. Montagnet angustifolia by Rosen- 
vinge, and with others named D. Holmiana by Strömfelt. 
'The references to this variety would appear to be as follows: 
DELESSERIA DENTICULATA Var. ANGUSTIFOLIA (Lyng.) Collins. 
D. alata B angustifolia Lyngbye, Tent. Hydr. Dan., p. 8, 1819. 
D. Holmiana Strómfelt in Holm, Beiträge zur Flora Westgrónlands, p. 
286, 1887. 
D. Montagne: B angustifolia Rosenvinge, Grénlands Havalger, p. 803, 1893. 
PiLINIA RIMOSA Kützing, Phyc, Gen., p. 273, 1843. 
The original description of this genus and species is as follows : 
“ Pilinia. Trichomata hologonimica, radicata, erecta, ramosa, fascicu- 
lata, in stratum spongiosum coalita. .. rimosa. P. crustacea, ligni- 
cola, primo porosa, deinceps rimosa, olivaceo-virescens, ¢richomatibus 
tenuissimis (diam. 545”) ramosis, articulis diametro aequalibus." 
It appears with practically the same description in Kütz. Sp. Alg., 
p. 425 ; in Tab. Phyc., Vol. IV, p. 20, Pl. XC, figs. 1-19, there is no 
description. 
In Rabenhorst, Fl. Eur. Alg., Sect. 3, p. 386, 1868, the description 
