334 WILLIAMS: PERUVIAN MOSSES 
BRACHYTHECIUM STEREOPOMA (Spruce) Jaeg. 
San Miguel, on live wood, 1,830 m., July, 1911, Foote 48. 
RHYNCHOSTEGIUM AQUATICUM (Hampe) Jaeg. 
Urubamba, in water, 2,900 m., July, 1911, Foote 43; Arequipa, 
in water, June, 1911, Foote 44; hoe on wet rocks, July, 1911, 
Foote 45. 
RHYNCHOSTEGIUM CONOPHYLLUM (Tayl.) Jaeg. 
Urubamba, on rock, 2,900 m., July, 1911, Foote 46; San Miguel, 
on live wood, 1,830 m., July, 1911, Foote 47. 
NEw YorK BOTANICAL GARDEN 
Explanation of plates 17-20 
PLATE 17 
Leptodontium integrifolium. 1. Plant about natural size. 2. Perichaetium, 
* 7. 3. Stem-leaf, X 15. 4. One side of base of leaf, X 115. 5. Pegs: cells 
of leaf, X 240. 6. Apex of leaf, X 50. lier aes of rae x1 
Globulina se ear 8. Plant Aten natural size. 9. P he Io. 10, Stem- 
leaf, X 45. 11. Apex of costa and leaf, x ea00 TA nein on of leaf, X 230. 
13. Basal a on one side of costa, X 230. 14. Cross-section of stem, X 230 
is. Cross-section of leaf, 230. 
PLATE 18 
Tortula lacerifolia. 1. Plant about natural size. 2. Perichaetial ee X 25. 
3. Upper stem-leaf, X 25 4. A segment from the leaf-margin, X 13 ae 
of leaf on one side of costa, X 180. 6. Cross-section of leaf, X 180. 
Hygrohypnum peruviense. 7. Plant about natural size. 8. Cross-section of 
stem, X 130. 9. Basal leaf-cells on one side of costa, X 270. 10; 11. Stem-leaves; — 
25. 12. Median leaf-cells, x 270 
' PLATE I9 
Grimmia rivulariopsis. 1. Fertile and: male plant about natural size. 2. Cap- 
sule, seta and perichaetial leaf, X 20. 3. Calyptra, X 20. 4. Lid, X20. 5+ Part 
of peristome and rim of capsule, X 110. 6. Autheridia with leaf, X 20. 7: Upper 
part of stem leaf, X 180. 8. Stem-leaf, x 18. 9. Median cells of leaf, X 180. 
to. Cells in lower part of perichaetial leaf, X 180. 11. Perichaetial leaf, X 18. 
12. Median exothecal cells, X 180. 13. Cross-section of stem-leaf, X 180 
PLATE 20 
yum biforme, 1. Fertile and male plant about natural size. 2- Mey 
plants, X 20. 3. Capsule, moistened, X 8. 4. Upper stem-leaf, X 16. 5: Out d 
perichsetial bas, X16. 6. Upper es of wieeten x 13s 7. Borges of leaf an 
adj 
9. Stoma, X 135. 10. Median exthea cells ae 436.  11., Patt of pest ristome, 
annulus and rim of capsule, x to : 
