430 MESSRS. J. PARKIN AND H. H. W. PEARSON ON THE 
The Botany of the Ceylon Patanas.—II. By J. Parkin, M.A., 
F.L.S., Trinity College, Cambridge ; aud H. H. W. Pearson, 
M.A.,, F.LS. 
(With Prarzs 11 & 12 and TaBxz.) 
[Read 19th March, 1903.] 
ConTEnTs. 
Page 
I. Introduction ..............cccceseceeeesees Meee ecccececeeceessencee veneeenereeeees 430 
TT, Table ......... cc ccceccecccsec sec ececetecneccnenereeeeeceesesasneneseceee see seee ees 434 
TIT. Explanation of Table ...........ccccceecececctceceeeececeeceeeraeceeceeesnnees 438 
IV. General Summary of the Anatomical Characters of the Leaf........- 439 
(1) Depth of the Upper Epidermis...........-..cseeeescssecerenteess 439 
(2) Thickness of its Outer Wall ..............sceceeceerenseeeeoerernes 440 
(3) Depth of the Lower Epidermis............sssccssecseseeceeesereee 440 
(4) Thickness of its Outer Wall ............scceceseseceeeeeeceeesenee® 441 
(5) Convexity of the Outer Wall of the Upper Epidermal Cells. 441 
(6) Waviness of the Lateral Epidermal Walls ...........:+++::++ 442 
(7) Stomata—their distribution, number, KC. ........eseeeereeeees 443 
(8) Mesophyll—its differentiation, thickness, intercellular 
BPA, KC... .eececescscscecscececcecscsceccesecerenensneaseeneseesent 
V. The “ Wet” and “ Dry” Patana plants compared with respect to 
the above Characters ........cscccoscescccscscceccteceecnecesecsanneesee® 445 
VI. Remarks on the Structure of Erect and Semi-erect Leaves..........-- 450 
VII. Special points in the Anatomy of the Leaf bearing on Xerophytism. 453 
(1) Double-layered Upper Epidermis or Hypoderm .......----- 453 
(2) Peculiar Lateral Walls in the Epidermis of Hypericum 
MYSOTENSE oo .ccecccecnceeccuccecceseccececnesecsanesee teense eeeeee eee 453 
(8) Mucilaginous Epidermal Cells............c:cseereeeenerenereeeee? 454 
(4) Chloroplasts in the Lower Epidermis ...........-s++e+ssrer00"* 455 
VIII. Additional points of Anatomical and Physiological Interest ...------ 456 
(1) Tannin Idioblasts in the Mesophyll............s0:+ecsseeeeeeest 456 
(2) Thick-walled Spongy Tissue in the Leaf of Mussenda 
SrOnd0sd vo .ccecceesees Ldeceescececcevcnsecssecscecncesesesseseeeee® 457 
(3) Crystals oo... ccc cccceeseceeeesccecceeeeeconsseccesnaneeeeeeeereeeses 457 
(4) Reserve Carbohydrates—“ red” starch, &c. ....sceeseerrrree* 457 
(5) Cortical Bundles in the Stem of Glochidion zeylanicum ..- 458 
6) Stipular G -ewelli is verticillaris. 459 
Ix. Sum ) ipular Glands and Root-swellings of Hedyotis vertect * 459 
re ee So ad 
Merde c eter en srerecseecccreetaresrerressesnsrsecvesessesaererrere® 
I. Inrropuction. 
In a former paper * some account was given of the grass 
lands, locally known as “ Patanas,” which cover a large part of 
the surface of the montane region of Ceylon. This paper was 
the outcome of investigations carried on by one of us én situ in 
1897. In the opening paragraph the purpose of the research 
was thus stated: “to ascertain (i) the probable causes which 
have led to the development of these remarkable sayannab-like 
* Pearson, Journ. Linn. Soe., Bot. xxxiv. (1899) pp. 300-365, with Map. 
