44 PROF, JULIUS MACLEOD ON TEN 
Taste XVIII. 
Description of Mnium orthorrhynchum, Bruch, Schimp. & Guemb. 
A.—Specific limits of variation. 
[ Boulder, Engstligen Falls, Adelboden (Switzerland).—H. N. Dixon dedit. | 
1. Length of the leaves: 3:00-5:41 mm. 
2. Breadth of the leaves: 0:30-1:03 mm. 
3. » T » at their base: 0:31-0:56 mm. 
4. d. » cells: 12-15 y. 
5. Number of cells: 21-62. 
6. Breadth of the border: 23-45 w. 
7. Number of cells of the border: 3-7. 
8. j marginal teeth: 22-38. 
9. m double marginal teeth: 12-31, 
10. m teeth on the nerve at the back of the leaves; 0-11. 
11. Length of the nerve: in 48 leaves I found the nerve reaching the summit; in 2 leaves 
merely a trace of connection between nerve and summit. 
12, Tooth at the summit of the leaves: always existing. 
13. Number of leaves: 25-61. 
14. j fruits: always 1. 
B.—Gradation of the characters. 
[One patch : Adelboden, 8 stems.] 
Mean interval curves. 
Intervals: 1. 9. 3. 4. 5. 6. Ë 8. 9. 10. 
Length leaves (mm.)...... 0776 099 1:23 141 1:59 2:00 2:84 2:91 319 3:96 
Breadth leaves (mm.) .... (0:36 0:42 0:50 0:56 0:65 0°84 0:93 0°93 083 0:64 
5 Dasa (W) o) s. 0:381 034 036 038 0'41 048 049 0'47 042 0'40 
3j COS (ies cas. TL T 12 12 13 14 14 14 14 13 
Number cells ........ c aM wm yz p M 5» wo 60 b2 o 
Breadth border (u)........ 24 27 28 28 28 31 33 34 36 33 
NPOLIMIDOLGOD T ree 5 6 6 6 6 6 6 6 6 5 
Marginal teeth .......... 1 2 5 (i 10 15 21 26 26 29 
Double marginal teeth .... 0 04 18 3 5 WwW 15 18 19 20 
Teeth nerve...... EAA s 0 0 0 0-702059 1 2 3 4 
een pth Nerves. ou. ss. .« t— t- +— +- t- +t += +- +t + 
Tooth summit...... Iw Ue E b LGB + + +4 
