415. L. Candida, (Web.) Ach.

Upon earth in the extreme north.

Arctic America. (Richardson.) Greenland. (Vahl.) On rocks, Deer Park, Lower Arrow Lake, Columbia River, B.C. (Macoun.)

416. L. caeruleo-nigricans, (Lightf.) Schaer.

On earth along the River St. Lawrence, Lat, 480. (Pringle.) On earth on Moose Mountain, Rocky Mountains, July 3rd, 1897. alt. 6,500 feet. (Macoun.)

417. L. cumulata, Sommerf.

On the earth in alpine and arctic regions. Greenland. (Vahl.)

418. L. squalida, (Schleich.) Ach.

On the earth in alpine and arctic regions, Greenland. (Vahl.)

418a. L. flavo-virescens, (Dicks.) Borr,

Parasitic on the thallus of Boeomyces Byssoides. Greenland. (Arct. Man.)

419. L. pruinosa. (Smith) Flot,

On rocks, Middle Greenland. (Eberlin.) On rocks, Birchy Cove and Irishtown, Newfoundland. (Waghorne.) On rocks along Jumping Pound Creek, Rocky Mountains, June, 1897; on sandstone rocks, Wood Mountain, Assa., June, 1895; quite com mon on granite boulders at Ottawa, Ont, and Hull, Que. April, 1897. (Macoun)

420. L. lapicida, (Ach.) Nyl.

Closely related to L. pruinosa.

Labrador or Newfoundland. (Waghorne fide Eckfeldt) Greenland. (Arct. Man.) On limestone shingle near the Hogsback, by the Rideau River, near Ottawa, Ont., May 7th, 1897; quite common on limestone rocks everywhere around Ottawa; at Wood Mountain, Assa., June, 1895. (Macoun.)

421. L. tessellata, Floerke.

Granitic rocks. Greenland. (Vahl.) Labrador or Newfoundland. (Waghorne fide Eckfeldt.) Along the north shore of Lake Superior. (Agassis.) On rocks along the South Saskatchewan River, Assa. (Macoun.)

422. L. tessellina, Tuckerm.

On various rocks. On boulders at Belleville, Hastings Co., Ont., Sept., 1878; along the Nipigon River, Lake Superior, July, 1884. (Macoun.)

423. L. auriculata, Th. Fr.

Granitic rocks, Greenland. (Vahl.) Arctic America. (Fries.) Labrador or Newfoundland. (Waghorne fade Eckfeldt.)

424. L. polycarpa, Fr.

On alpine and arctic rocks.

Labrador. (Krempelhuber.) Arctic America. (Stizenberger.) Labrador or Newfoundland. (Waghornefide Eckfeldt) On rocks, Deer Park, Columbia River, B.C., June, 1890. (Macoun)

425. L. variegata, Fr.

On rocks, Labrador or Newfoundland. (Waghorne fide Eckfeldt)

426. L. panoeola, Ach.

On granitic rocks, Greenland. (Vahl) On rocks, Labrador or Newfoundland. (Waghorne fide Eckfeldt)

427. L. contigua, Fr.

Greenland. (Arct. Man.) On rocks, Labrador or Newfoundland. (Waghorne fide Eckfeldt.) Granite rocks, along Ste. Anne des Monts River, Gaspé Co., Que.; on limestone rocks at Aylmer, Que., April 25, 1900. (Macoun)

428. L. speirea, Nyl.

On rocks, north shore of Lake Superior. (Agassiz.).

429. L. confluens, Schaer.

Granitic rocks in alpine and arctic regions. Greenland. (Vahl.) Arctic America. (Richardson.)

430. L. albocaerulescens, (Wulf.) Schaer.

Granitic and arenaceous rocks.

Labrador or Newfoundland. (Waghorne fide Eckfeldt.) On granitic rocks at Shannonville, Hastings Co., Ont.; on granitic rocks at Margaree, Cape Breton Island, N.S., July, 1898. (Macoun.)

Var. flavocaerulescens, Schaer.

On rocks in alpine and arctic regions.

Labrador or Newfoundland. (Waghorne fide Eckfeldt) On rocks along the Ste. Anne des Monts River, Gaspé Co., Que., Aug, 18th, 1882. (Macoun.)

431. L. atro-brunnea, (DC.) ScHaer.

On alpine and arctic granitic rocks. Greenland. (Vahl.)

432. L. fusco-atra, (Linn. Fr.

Granitic rocks, alpine and arctic, as well as in the lower districts.

Greenland. (Arct. Man.) Arctic America. (Richardson.) Tadou-sac, St. Lawrence River, Que. (A. T. Drummond.) Labrador or Newfoundland. (Waghorne fide Eckfeldt.)

433. L. tenebrosa, Flot.

On rocks, Labrador or Newfoundland. (Waghorne fide Eck-feldt)

434. L. fuscescens, Sommerf.

Greenland. (Arct. Man.) On rocks, Labrador or Newfoundland. (Waghorne fide Eckfeldt)

435. L. Dicksonii, Ach.

On rocks, Sparrible Cove, Newfoundland. (Waghorne.)

436. L. polygonia, Flot.

On rocks, Leading Tickle, Newfoundland. (Waghorne.)

437. L. Armeniaca, (DC.) Fr

Alpine and arctic granitic rocks, Greenland. (Vahl.)

438. L. aglaea, Sommerf.

Alpine and arctic granitic rocks. Greenland. (Vahl.)

439. L. amylacea, Ach

Alpine rocks, containing lime. Greenland. (Vahl.)

440. l. enteroleuca, Fr.

On rocks and stones.

On stones, Rofe Cove, Bay of Islands and Little Harbour,. Newfoundland. (Waghorne.) Greenland. (Arct. Man.) On small pebbles at Baddeck, Cape Breton Island, N.S., July 29th, 1898; on small stones, summit of Mount Albert, Gaspé Co., Que., 1882; on small pebbles at Ottawa, Ont., April, 1900. (Macoun.)

Var. sequata, Flcerke. On trap rocks, Grand Manan Island, N.B. Willey.

Var. muscorum, Koerb,

Chiefly on mosses in alpine and arctic regions,

Islands in Behring Strait. (Wright.) On moss at the bases of trees, Salt Lake, Anticosti, Que.; on earth in woods at Banff, Rocky Mountains, 1891. (Macoun.)

Var. achrista, Sommerf.

On trees and shrubs.

On bark of trees along Lake Winnipegosis, and on Moose Mountain, Man., July, 1880; on cherry bark at Old Wives' Creek, Assa., May, 1895; poflar bark along Jumping Pound Creek, Rocky Mountains, June, 1897. (Macoun.)

Var. pilularis, DC.

On limestone rocks along the Rideau River near the Hogsback, May 7th, 1897; at Aylmer, Que., April, 1900. (Macoun.)

441. L. vorticosa, Koerb.

On alpine and arctic granitic rocks. Arctic America. (Fries.')

442. L. pycnocarpa, Koerb.

Granitic rocks, Island of Grand Manan, N.B. (Willey.)

443. L. arctica, Sommerf.

Upon mosses in alpine and arctic regions.

Greenland. (Vahl.) Islands in Behring Strait. (Wright.)

444. L. planetica, Tuckerm. var. perfecta, Eckfeldt.

On limestone shingle at Britannia, near Ottawa, Ont., April 20th, 1895. (Macoun.)

445. L. limosa, Ach.

On naked earth in alpine and arctic regions. Greenland and Arctic America. (Fries.)

446. L. alpestris, Sommerf.

On earth in alpine and-arctic regions.

Greenland and Arctic America. (Fries.) Greenland. (Arct. Man.)

44V. L. assimilata, Nyl.

On earth in alpine and arctic regions. Islands of Behring Strait. Wright.)

448. L. melancheirrut, Tuckerm.

On dead wood in Canada. (A. T. Drummond.)

449. L. crassipes, (Th. Fr.) Nyl.

Upon mosses in alpine and arctic regions. Arctic America. (Th. Fries.)

450. L. Morio, Schaer. var. covacina, Schaer.

On alpine and arctic rocks. Arctic America. (Dr. Kane.)

451. L. aromatica, (Swartz.) Ach,

On rocks, Lake Nipigon, Ont., July 9th, 1884. (Macoun.) This species was named by Tuckerman and belongs to the section Toninia.

452. L. crenulata, (Dicks.) Eckfeldt.

On rocks, Labrador or Newfoundland. (Waghorne fide Eckfeldt.)

453. L. crustulata, Ach,

On rocks, Labrador or Newfoundland. (Waghorne tide Eckfeldt.)

454. L. distans, Eckfeldt,

On rocks, Labrador. (Waghorne fide Eckfeldt.)

455. L. empetrea, Nyl,

Labrador or Newfoundland. (Waghorne fide Eckfeldt.)

456. L. latypea, Ach.

On rocks, Chimney Cove, Newfoundland. (Waghorne.)

457. L. Kochiana, Hepp,

On rocks, Labrador or Newfoundland, (Waghorne fide Eckfeldt)

458. L. dispansa, Nyl,

On rocks, Labrador or Newfoundland, (Waghorne fide Eckfeldt)

459. L. sylvicola, (Flot.) Nyl.

Labrador or Newfoundland. (Waghorne fide Eckfeldt.)

460. L. conferenda, (Nyl.,) Eckfeldt,

On rocks, Labrador or Newfoundland. (Waghorne fide Eckfeldt.)

461. L. contracta, Th. Fr,

On rocks, Chimney Cove, Newfoundland. (Waghorne.)

462. L. plana, Lahm,

On rocks, Clark's Brook and Bay of Islands, Newfoundland. (Waghorne.)

463. L. sorediza, Nyl

On stones, Lark Harbour, Shoal Point and Ballantyne Cove, Newfoundland. (Waghorne.)

464. L. viridans, Flot.

On stones, Lark Harbour, Newfoundland, (Waghorne.)

465. L, parasema, Ach

On bark of trees, Wild Cove, Newfoundland. (Waghorne)

466. L. (Biatorina) synothea, Ach,

On old boards, Birchy Cove, Newfoundland. (Waghorne)

467. L. fusco-rubens, Nyl. Greenland, (Dr. Brown in Arct. Man.)

468. L. Discoensis, Linds.

Greenland, (Dr. Brown in Arct. Man.)

469. L. Campsteriana, Linds.

Greenland. (Dr. Brown in Arct. Man.)

470. L. Priesiana, Linds.

Greenland. (Arct. Man.)

471. L. Egedeana, Linds.

Greenland. (Dr. Brown in Arct. Man.)

472. L. subfuscula, Nyl. Greenland. (Arct. Man.)