Sai pn ons = ately : ie a ae oe : Aso) THE GRASSES AND GRASSLANDS OF SOUTH AFRICA BY J. W. BEWS, M.A., D.Sc. Professor of Buea, in the Natal University College, Pietermaritzburg LIBRARY mEY YORK BOTANICAL (MARDER PIETERMARITZBURG : P. DAVIS & SONS, LTD., Printers, Longmarket Street. 1918. : ‘(os ule ) a ‘ es Aa 7a) a | | - | VELD REGION | SAND re 4 Hreams } ; Clesbepo KARROLD Sa edeathacocaay | Heke ro Weslo y CENTRAL “ WEast Londat; Ppslown | | Yat thzahelh i ———— | THE GRASS REGIONS OF SOUTH AFRICA. ScCate a. 2 Ca *ARY Preface. ORK a) The following pages have been written as a preliminary contribution to a very big and important subject. Various studies in South African plant ecology have been made during the past eight years, and to begin with it was my intention to add another to the series of papers, which I have published on this subject, namely, one dealing with the plant succession in the grasslands of South Africa. A grant towards travelling expenses was made by the Royal Society of South Africa. Various preliminary difficulties had first to be overcome, among which the chief one was the devising of a simpler means of identifying the 500 odd species of grasses, which occur in South Africa.. The Key as first drawn up, was not intended to be published, but when I had distributed a few manuscript copies, it was urged by several of those who received them that the key should be included in the publica- tion since it would prove useful to others. It is hoped that this will be the case, and at any rate it may be of assistance to those who are not in possession of the more elaborate treatise by Dr. Stapf in the Flora Capensis. It soon became clear as the work progressed, that many nportant economic questions were involved, and detailed reference to these added to the length of the paper, so that for various reasons it was thought desirable to publish it in book form rather than in one of the scientific journals, especi- ally since, under the present abnormal conditions, the sending of manuscript overseas leads to very long delays. I have to express my indebtedness to Mr. C. G. Smith, of Durban, who has made a generous grant towards the cost 4 of publication. To two of my students, Miss M. Batchelor and Miss K. Jameson, my thanks are also due for doing most of the work in connection with the preparation of the illustrations. The map was prepared by Mr. R. Walker. lv. Tt is too much to expect that a work of this kind will be free from mistakes, and I hope that readers will help me by pointing out any corrections that should be made, or by ofter- ing suggestions for the improvement of the key. Since, in the key to the species, and in the section of ecological notes the genera are arranged alphabetically, and a fan table of contents is given for fhe sections dealing with the plant succession and economic applications, it has not been thought necessary to add an index. J. Woe ise Natal University College, July, 1918. Contents. i. INTRODUCTION ...... .... sheen sie General dlosdaeaion * OUASSESR Pee ed Ee ateC Me oe Plant succession ... ... Bee Glossary of botanical seats SAE URE ARAL BATS OE ot fl. KEY TO THE GENERA AND SPESIES OF SOUTH ARIRIGAN GRASSES © 2.5 25 :c0c0 oes cece cow son ees Wey tothe. Speciesi:.: c45 thaush, eo vees lil. ECOLOGICAL NOTES ON THE PRINCIPAL SPECIES IN BAGH? GENUS poicis ais ccs se ook meee ae eon Aa rence GV. GENERAL SKETCH OF THE GRASSLANDS OF SOUTH AFRICA AND THEIR DEVELOPMENT... ... ... ... ... 1. SourH WesTERN or Care ReGcion oF Maccuia or FYNBOSCH EA MENGE NETO SOUCY stant aah ld er star tae wate mee. Rn, acy eee geet a at ERR ee Wine MEN VG rOserO ye: iN i aes. aos, outer sd nc tiee Seas Meee, eae Cather samimosener see acne Deeituderal Specieswor , STAsses) (ee, 220) asc wee soe tose The influence of man ... ... . : anidly See ate The extent of the South W ee RECHOML Sey tas ceeee alte Outhers in Namaqualand ... Poe eve VV PESDERN VEU BGIONG @ 4 ikoeunccccaduescs Pett) wich atl ean ote geen: A. Coast belt . Jone teel oe B. Higher Eisvations of the iene Namib Be eee es Moet C. Central and Eastern Mountain Ranges ... ... ... ... ... 1D}, Wordngmm Alinesis, A\imnloollenael 356 seo ooo ooo sun cob. Goo cee 3. THE Sanp VELD REGION Poy ih Se Ieee est nme oe RL Os 2 ME aret eye AVS IK laptop ORO, CaM pent Nab Neenet Mars AGREE! ARTES i) 4, Tue KarrRoo aND KarroiIp CENTRAL REGION ... ... Bee The boundaries of the region. Transitional ree scr The Karroo proper ... ... Bee The Mountain ranges of bhe iKeiteoo region ‘Tub TRANSITIONAL BELT BETWEEN KARROO AND HASTERN GRASSVELD he: XNerosere’... ... =. Haas-gras Veld . e Mountain grasses ead eased’) a he Praneiipanl belt . PAGE. a on wae PAGE. Syed HANDLE (CoV ASSN Gon PLO a OTERCOM Pee 5351 San pon, onplbehaslere cade cee ony LILO, Climatic factors.) cen | eee eee: Cine reece thea eencecey nf ex OT Oy MVC PRET OSELE I 2 3.) lire Se aE ce Oca eckrcdoees genie amish etd he mae Initial Grassland Stages eroneersGrasses ay see lalics Stable Grassland: “Climaxestaces ssc cs eee sees eee LUG) Influence of man. ‘‘Substituted types’”’ ... .. Be) eet (0) Aspect Societies and Clans in Eastern Giaeu alae. Bee at Prevernal: Aspects: ie cata ft coi e teeter: eee ee led Vernal Aspects ... ... She cual ie Mie aetna A Gln Aestival and eres Weseots Bre anesays 126 The Transition to Woodland. Post climax east aa 17 The Transition to Thorn Veld and Thorny Scrub ... ... 128 The Hydrosere ... ... : 129 Subseres in Cultivate ae or Wante. fond Ruderat Species 131 Other Subseres. The Plant Succession in Dongas ... 134 THe Coast Brett anpD Coast LINE oF NatabL .:. ... ». 01... ... Tass The Psammoseres) )Litoral sspeciess shea eee eee 135 Mie Xerosere:. 72204, labak cay ete ae OO ee ee Eee (he ‘Hydrosete \.32, 55 .ahescan ne carat ot om aee eee OS hey Halosere' s\:.0..300 SUA cody ei dd sean paciiy Rit ae Eee eae eS Mountain Tussock GRASSVELD ... ... sjeatihoyy ise ead ten Other mountain species of the ‘Drakensbere Ba nese tbs ies 140 Vv. ECONOMIC APPLICATIONS .... 50.5.2. 230% 2060-0) fee 2 le Grass (DOEMIDG 15. Fiche tesa deerme ae ce mane aa tena me aa Stock grazing ... ... Ly aS The feeding value of vditerent iypes: of spuneelanas and BMASSOS. 0 1siiee cee cab cele geo aa ati RE a OME EC RE ee They cultivation, of erasses..2..).: lose ce: eo eeeee tees eae SOR PH OSTOM ais a aid aa ok een ee ec een rae a tea LL APPENDIX. LIST OF ENGLISH, DUTCH, ZULU, AND SESUTO NAMES OF GRASSES ...... ... ... ... ... 2. ... 16k Introduction. The grasses belong to the family of the Poaceae or Gramineae, a well-defined natural group of plants. They are found all over the world, and altogether over 3,000 species are known. In South Africa there are about 500 species, a few of which have been introduced since the advent of the white settler. from the economic standpoint no family of plants is of greater importance since the Gramineae include the cultivated cereals, and the natural grasses are the chiet food of stock 11 a pastoral country such as South Africa. The study of the individual species is not simple even for the expert, since they are separated by somewhat artificial char- acters, and the tribes into which they are divided are not well defined. On the other hand the collections of South African grasses that have been made are remarkably complete as com- pared with some other families. The earliest collections were made by Ecklon, Zeyher and Drege, and these were worked up and descriptions were published by Nees in 1841. Since that time many new species have been discovered, and the whole group has been thoroughly revised, and careful descrip- tions of the individual species have been given by Dr. Stapf in the Flora Capensis. Medley Wood in ‘‘Natal Plants’’ has given illustrations of 200 species, but he added little to Dr. Stapf’s descriptions. Stapf has also written an interesting phytogeographical sketch of the distribution of the various genera and tribes in the separate regions of South Africa.! Though these works have been eodenle for many years, there are very few in South Africa who are familiar with the orasses. Students of Botany, I find, experience great diffi- culties in making use of the key to the genera given in the Flora Capensis, not that the work differs in that respect from other similar manuals. Many of the statements in all such keys are found on close inspection to be vague and contra- dictorv. When I began a study of the plant succession in the grasslands of Seuth Africa, I became convinced of the neces- sity of devising a simpler means of recognising the different erasses, and consequently + the artificial key which is given here was drawn up. The nomenclature adopted throughout i is that of the Flora Capensis, since a work of this kind is hardly the place where any revision of nomenclature should be under- taken. 1. Stapf, O. “ Die Gliederung der Griserflora von Siidafrica.” Festchrift Ascherson, Berlin, 1904. 2 To make the key as useful as possible to the reader, who is not familiar with botanical terms, a glossary is added, and the following elementary description of the structure of grasses is given. (See also Figs. 1 and 2.) Fig. 1—B. Festuca elatior. Spikelet with two lower florets opened out. a Lower glume. b Upper glume. c Valve. d Pale. 8B. Festuca elatior. Floret with Valve removed. a Pale. b Lodicules. c Stamen. d Ovary with two feathery styles. C. Eragrostis superba. Spikelet. a Lower glume. b Upper glume. c¢ Valve. Numerous florets in the spikelet far exserted from the glumes. D. Achneria capensis. Spikelet. a Lower glume. b Upper glume. c Valve of lower floret. d Pale of lower floret. e Valve of upper floret. / Pale of upper floret. Two florets enclosed in the glumes. E, Azxonopus semialatus var. ecklonii. Spikelet. a Lower glume. b Upper glume. c Valve of male floret, d Valve of the perfect floret. e¢ Pale. Only one perfect floret, with one male floret below it. F. Aristida bipartita. Spikelet. a Lower glume. b Upper glume. c Valve with 3 branched awn. Only a single floret in the spikelet. G. Andropogon wpertusus. a Sessile floret with lower glume pitted. Awned. b Pedicelled floret usually male. Awnless. (Figs A. and B. after Strasburger). 3 The ultimate branch of the inflorescence of a grass is the spikelet which is either borne on a stalk (or pedicel) or if there is no stalk is said to be sessile. It consists of an axis, known ‘as the rachilla, which bears modified leaves or bracts arranged alternately. The lowest two bracts have no flowers in their axils and are known as glumes, the succeeding bracts have flowers, and are known as valves. There are, however, the following occasional variations: (1) one or Roth the glumes may be yeene or minute, and (2) one or more of the valves may have the flower imperfect or absent altogether. In the latter case the valve resembles a glume and is said to be empty or barren. Either the glumes cr the valves may be prolonged down- wards at the point of their insertion on the rachilla into a callus. Either the glumes or the valves or both may be prolonged upwards into a short mucro or longer ain. Between each valve and ihe axis there is another bract called the pale which is sometimes small or absent. The ‘flower is borne between the valve and the pale. The separation of the different species depends chiefly on the characters of the glumes and valves, and the mode of arrangement of the spikelets in the inflorescence, but some- times the characters of the flowers or seed are of importance. The perfect (or hermaphrodite) flower consists of two minute scales called the lodicules, usually 3 stamens (rarely 1, 2, 4, or 6), and a single ovary. Each stamen consists of an anther, borne on a slender filament. ‘The ovary bears two ‘feathery styles (rarely 1 or 3). Male flowers have stamens only. Female flowers have ‘the ovary only. The fruit (or so-called seed) is called a caryopsis, and has the seed coat adhering to the fruit wall. In a few cases ‘the seed is free inside the fruit wall, and the fruit is called a utricle. The flowering axis is the culm. In perennial grasses there are innovation shoots which grow into culms in the second year. The innovation shoots either pierce the sub- ‘tending leaf sheath, and grow up outside it (extravaginal), or they erow up between it and the culm (intravaginal). This feature is important in connection with plant succession and ‘in the study of the effects of grass burning, etc. 4 The leaves are arranged alternately in two rows (2 ranked) and when perfect consist of (1) a sheath with its margins over- lapping or grown together surrounding the culm, (2) a blade, and (3) a ligule, which is placed transversely at the inside of the junction of the sheath and blade. F Fig. 2.—Forms of inflorescence. A. Oropetium capense, a portion of a simple spike. B. Harpechloa capensis, a single secund spike. CU. Eleusine indica,. secund spikes. D. Setaria perennis, a panicle (false spike). E Andropogon hirtus, a single pair of racemes from the panicle. EF. Sporobolus festivus, var. stuppeus. A portion of the panicle (A. magnified, the others slightly reduced). The inflorescence consists of (1) a spike if the spikelets are not stalked (sessile), or (2) a raceme if the spikelets (or- 5 some of the spikelets) are stalked, or (3) a panicle if the maim axis is repeatedly branched bearing racemes laterally. The identification of grasses is quite impossible unless. the dissection is proceeded with in the proper way. Very little apparatus is required. A cheap mounted lens costing a few shillings is necessary. It should be placed over a glass. plate, on which it is convenient to have the measuring scale in lines (equal to 1-12th of an inch) scratched out or etched. The spikelets should be dissected by means of two mounted needles (or large unmounted darning needles will serve) im a drop ot water, “and the characters of the separate parts noted as they are removed. Special care should be taken with the nerves or veins in the glumes and valves. These are sometimes. faint, and can only be seen when the part is immersed in a drop of water. In the sections where the environmental or ecological relationships of the grasses, and the development of (or plant succession in) the grassland types of vegetation are dealt with, certain other ae are used, and a bier introduction to thie section is also necessary. The most recent work on this impor- tant aspect of botanical science is a book on ‘‘Plant Succes- sion’? by F. E. Clements, by consulting which fuller details may be learned. His system of nomenclature is adopted as far as has been found convenient. The important idea that must be grasped at the outset is that the development of the vegetation must be studied, and it is only in so far as we understand it fully that light will be thrown on many extremely important economic problems. The composition of erass veld, as farmers know well, is very apt to change, and it is one of the chief objects of this work to endeavour to explain, at least to a certain extent, what are the underlying causes which bring about such changes. The effects of grass burning, for instance; can only be properly understood if the detailed plant succession in the veld has been carefully studied. The Formation is the final phase of a succession, or climar plant community over a natural area, in which the essential climatic conditions are similar or identical. Examples of plant formation in South Africa are:—(1) the Macchia of the South-Western portion of the sub-continent consisting chiefly of hard-leaved (sclerophyllous) shrubs. It occurs also at higher altitudes along the Drakensberg. In it a large number of drought- resisting (xerophytic) grasses are present, but they occur in isolated tufts, or small patches, and 6 are nowhere dominant, (2) open grassland formation of the Western side. much of it semi-desert, (3) the Karroo, (4) the Sand Veld of the Kalahari, (5) the Grarsveld of Eastern Cape Colony, Natal, the Eastern part of the Free State, and the Transvaal, a widely extended type of formation of which there are several sub-types or varieties which may or may not be considered sufficiently distinct’ to rank as separate forma- tions. (This type will often be referred to in the following pages as “‘the grass veld of the Eastern side’’ or “astern erass veld’). (6) Succulent and Thorny Scrub of the dry river valleys—the climax of Thorn Veld, (7) Forest. The Association is a climax community with two or more dominants, e.g., a Yellow-wood-Black Ironwood forest. The Associations are units which are associated regionally to con- stitute the formation. The Consociation is the unit of the association charac- terised by a single dominant, e.g., Falcate Yellow-wood forest Anthistiria (red grass or insinde) veld. The Society is a climax community characterised by a sub-dominant, or sometimes by two or more sub-dominant species. Societies of various species of the large grass genus Andropogon are very common in much of our eastern grass veld. The society is a localised or recurrent dominance within a dominance. Clements distinguishes (1) Aspect Societies which dominate only for a season, e.g., in spring and are replaced later by other societies. We thus find Pre- vernal, Vernal, Aestival, and Autumnal aspect societies. Of these the vernal and aestival are of most importance in South African grass veld. (2) Layer Societies very conspicuous i woodland but occurring in grassland also. The different types of vegetation are arranged in layers, and the develop- ment is usually seasonal as in the aspect societies. (3) Crypto- gamic Societies consisting of lower forms of plant hfe such as the Mosses. The Clan ranks below the society in importance, but there is no hard and fast line to be drawn between them. The clan is local or restricted to a few scattered areas. It is necessary to lay emphasis on the fact that all the above are climax communities, belonging to the final stage of the plant succession. Throughout the succession there are similar or analagous communities, which do not belong to the climax stage, but Pls ( prepare the way for other communities which succeed them-~ For these Clements proposes other terms, viz., Associes,, Consocies, and Socies, these being the developmental or seral equivalents of Association, Consociation and Society. Further a Colony is a pioneer or initial community of two or more species, and a Family according to Clements, in the ecological sense is a group of individuals belonging to a single species, which usually soon becomes converted into a colony. This. last term is likely to lead to confusion, since it is also used in another sense, so it will not probably be generally adopted. ‘ Instead of using the term “‘succession’’ both in a concrete and in an abstract sense, Clements uses the word Sere as a term for a definite single or unit plant succession. It comprises the: development of a formation from the appearance of the first pioneers through all the stages to the climax. The various. successions are further seeded into Primary and Secondary with the corresponding terms Prisere and Sub-sere. Priseres are the main regional successions, and their analysis is not always easy. Swb-seres are confined to bare areas due to super- ficial disturbance, and are largely due to man’s interference. For example: the succession from abandoned cultivated land back to grassveld is a Sub-sere, as is also regeneration in a burnt-out forest. The Sub-seres are much more numerous and more easily investigated than the Priseres. Priseres and Sub-seres are further sub-divided according to the nature of the extreme area which is colonised by the- initial or pioneer communities, into (Ll) a Hydrosere which begins in wet places such as Vleis, and (2) a Xerosere which begins in dry places. There are other proposed terms, v7z., Halosere for salt water, Orysere for acid water, and the Xerosere may be divided into Lithosere for rock surfaces, and_ Psammosere for sandy areas. (oa) Glossary of Botanical Terms. Acuminate point. Acute—simply pointed. Adnate—crowing to something else. Amplexicaul—stem clasping. Anastomosing—joining up veins. Aphyllous—leafless. Aristate—awned. Aristulate—with a small awn. Articulate—jointed. Ascending—rising upwards as a stem. Auriculate—ear-shaped. to tapering a long or upon of Caducous—falling off. Caespitose—growing in tufts. Capillary—hair like. Cavitate—head shaped, with a head. Caudate—tailed, with a tail. Chartaceous—paper-like, papery. Chlorenchyma—tissue with green chlorophyll. Ciliate—tringed with Cilia, as with eye lashes. Clavate—club-shaped, thickened upwards. Conduplicate—simply folded. Connate—united or growing together. Convolute—inrolled. Cordate—heart-shaped, with rounded lobes at the base. Coriaceous—leathery, leather- like. ‘Crustaceous—slightly brittle. Cuneate—wedge-shaped. Cuspidate—tipped with a short rigid point. Decumbent—reclining with the summit ascending. Decurrent—running down. Deltoid—in the form of an equi- lateral triangle. Dentate—toothed, teeth pointing outwards. Denticulate—minutely toothed. Dichotomous—with forked branching. Diffuse—loosely spreading. Digitate—arranged like fingers of a hand. the Distichous—having two rows. Divaricate—widely — spreading apart. Divergent—spreading in different directions. Dorsal—pertaining to the hack. Effuse—loosely spreading. Eglandular—without glands. Emarginate—having a apex. Erect—upright, perpendicular. Evanescent-—lasting only for short time. Excurrent—running out. Exserted—projecting beyond. Fascicled—in close clusters bundles. Fastigiate—with parallel clustered branches. Filtform—shaped like threads. Fimbriate—with a fringed margin. F !abetlate—fan-shaped. Fugacious—falling off or fading early. Fusiform—tapering at both ends. Geniculate—kneed and bent. Gibbous—humped or pouched. Girders—supporting bands Sclerenchyma running in the principal ribs and ridges of a leaf. Glabrous—without hairs. Glabrescent—becoming hairless. Glandulose—with glands. Claucous—of a grey blue colour. Halophilous—salt loving. Halophytes—plants growing brackish soils. notched erect Heteromorphous—of more than one kind or form. Hilum—scar on seed where for- merly attached, a posterior mark on the grain (caryop- sis) of a grass. Hirsute—rough, hairy, with long distinct hairs. Hispid—with stiff hairs or bristles. Hyaline—olass-like, transparent. Hydrophilous—water loving. Hydrophytes—water plants. Hygrophiious—moisture loving. Hygrophytes—plants growing in moist places. Imbricate—overlapping. Involucre—a covering of bracts. Involute—rolled inwards. Lanceolate—narrow. and _ taper- ing at both ends. Lax—loose, spikelets some dis- tance apart. Linear—at least five times as long as broad, with parallel straight sides. Membranous—having the texture of fine membranes. Mesophytes—plants adapted to fairly moist conditions. Mucronate—with a short point (mucro) suddenly springing from a rounded apex. Mucronulate—with a little mucro. Muricate—full of rough, short, sharp points. Muticous—curtailed, blunt, awn- less. Obtuse—blunt and rounded at the apex. Ovate—elliptic but broader at the base. Pectinate—like the teeth of a comb. Peduncle—stalk of flower or inflorescence. Penicillate—brush-like, or pencil shaped. Pericarp—fruit coat. Pilose—thinly covered with long soft hairs. Plicate—folded like a closed fan. Plumose—feathery plumed. Praemorse—as though the end were bitten off. Procumbent—lying ground. Pruinose—having a waxy bloom on the surface. Psammophytes—sand plants. Pubessent—slightly hairy. Punctate—marked with dots. Punctiform—like a dot. Pungent—pointed, piercing. along the oD Radical—belonging to or arising from the root. Reflexed—abruptly bent back. Retuse—blunted with a slight notch at the rounded apex. Revolute—rolled back from the margin or apex. Rhizome—an underground stem. Rigid—stiff, inflexible. Ruderal—crowing in waste places. Rufous—reddish. Rugose—wrinkled. Sagittate—with lobes at the base pointed like an arrow head. Sarmentose—bearing long slen- der runners. Scabrid—rough to the touch. Scaberulous—somewhat rough. Scarious—dry and membranous, not green. Sclerophyllous—with hard _ stiff leaves. Sclerosed—hardened, lignified. Sclerenchyma—hardened fibrous tissue. Sesund—one-sided, on one side. Serrate—beset with saw teeth. Teeth pointing forwards. Setaceous—like coarse bristles. (Seta—a bristle.) Setose—bristly, beset with bristles. Sessile—without a stalk. Sinus—a deep notch or recess. Spathe—a large bract enclosing a flower cluster. Spicate—disposed on a spike. Spiciform—like a spike. Spinescent—ending in a spine. Stellate—star-like. Stipitate—having small stalks. Stoloniferous—having suckers or runners (Stolons). Striate—with fine longitudinal parallel veins. Strigose—closely bristles. Subulate—awl shaped; than setaceous. Suffrutescent—somewhat like a shrub. Sulcate—crooved, fluted. Supine—prostrate. covered with stouter furrowed, or Terete—cylindrical, circular in cross section. Testa—seed coat. Thyrsoid—a compact cence, thicker at the middle and tapering at both ends. Tomentose—densely covered with short soft tangled hairs. inflores- 10 Trichotomous—with divisions im threes. Trigonous—three cornered. Trimerous—in _ three parts in threes. Truncate—ending abruptly as if eut off. Tuberculate—heset with knobby projections. Turgid—swollen, but not hollow. angled, three- parts, or small Umbelled—arising near point, in an umbel, one Ventral—pertaining to the front. Villose or Villous—shaggy, with long soft hairs not inter- woven. Viscous—Vissid—sticky. Viviparous — producing young plants instead of seed. Xerophilous—adapted to with- standing drought. Xerophytes—plants which live under dry conditions. Jud II.—Key to the Genera and Species of South African Grasses. (a). Spikelets all sessile singly or in clusters in the notches of a simple spike, not all on one side of the Rachis; ssecund weiribe Hordeae) see Bist 2 Ack. 22 (b). Spikelets sessile or slightly pedicellate, all on one side Oltne rachis(secumed), see his. 2B. and Ca 7 ‘c). Spikelets neither in the notches of a simple spike nor Sccumde See Nig’ 2 WO. ee am Gel caaeincen aie tee) 20 .2. Two or more spikelets at each node of the spike. Hordeum. spikelets solitary at the nodes of the spike ............. 3 3. side of the spikelet towards the rachis... ... .:. 4 Edge of spikelet towards the rachis. Lower elume. minute ONO are tah P oeve e setae Peso sis ) . Glumes subulate, { nerved . SSRN = Secale ‘africanum. Glumes not subulate, many nerved . Agropyr rum - distichum. 5. Flowers 3-many in the spikelet. Valves 5-7 nerved. Lolium. Flowers 1-3 in the spikelet. Valves 1-3 nerved ... ... 6 Galinper glume 5-7 merved: ... 22.22: Lepturus cylindricus. Upper glume 3 nerved ... ... ... ....... Oropetium capense. . Two empty valves between the glumes and the perfect florets. Spikelets falling entire with the glumes... 8 1-0 empty valves between the glumes and the perfect florets, or if 2 barren florets occur oe then the elumes Persistent... 2-5 = gy oes 8. Glumes and empty valves. one nerved.. _ Tetrachne dregei. Glumes and empty valves more than one nerved. Entoplocamia aristulata. -1 9. Valves one nerved. Strand plant ... ... Spartina stricta. Walves more than ome:nerved: 3.2) 8 2s. oe oe oot ols, 10 10. Spikelets falling entire. Lower glume smaller or O. CHES TOC MCC Cle Clem eces cae Lehane ee Mt ie tec ee ACD Lower glume persistent, distinct and keeled. Upper glume sometimes falling with the spikelet ... ... 14 11. Spikelets sunk in hollows or adpressed to the face of a broad rachis. Stem creeping. Stenotaphrum glabrum. Spikelets not sunk in hollows on a broad rachis ... ... Ae 2 12 12. Lower glume distinct.(See also 55).... ....... ... Panicum. Lower- glume minute.or Os... 2... 3.. Bry tked: ate 13 13. Nerves of lower value 5-7 close straight and prominent. Lower glume usually present but minute. Digitaria. Nerves of lower valve 5 or fewer. Side nerves curved and usually submarginal. Lower glume absent. Paspalum. 44. Spikelets 1 flowered. No male or barren florets ... 15 Spikelets with more than 1 perfect floret, or with 41 perfect and: i Or more male onrsbarren MOLetSier scat scuesae lO 15. Glumes shorter than the glabrous valve ... ... Gynodon. Glumes longer than the ciliate valve ... .... Microchloa. 16. Spikelets with 1 perfect and { or more male or barren or rudinmentarye MOoretsicce aioe snore ee edie sew ee iW Spikelets with 2 or more perfect florets ...’... ... ... 20 17. More than one spike in the infloresence ... ... ... Chloris. Sikee! SOMMATN sas coktestovescosceceee Sete ek a att aie pe eS 18; GSPUKOLCES SAVANE Coa) che) ss eld eet ees ~Cienium concinnum. Spikelets awnless- PoN satel te Shakira Soke Nai RR NC ec Aine 4 econ asim 19. Upper glume much longer ‘than the lower Harpechloa capensis Lower glume slightly Jonger than the upper Microchloa altera var. nelsoni. 20. False spikes numerous, arranged spirally ... ... ... 21 Spikes or false spikes solitary or eecene sometimes with 2 below the umbel . Cone Ne MPT RS NE 0 102.3, 24. Valves minutely notched. (See also 38) dot - Diplachne. Wallves: GCHLURG uae ch. 6 eee: hd bee ae 22. Tips of rachilla joints fring ed with ‘minute hairs. Pogonarthria faleata. Tips of rachilla joints not fringed. (See also 88). Eragrostis. 23. Inflorescence a single false spike ... See tee nee ben More than one spike in the inflorescence PR ASbe ee a 25 24. Spikelets 2, OW enedie4 >a ase Prionanthium pholiuroides. Spikelets 4-9 flowered. (See aiso 113) ... ... Brizopyrum. 25. Spikes terminated by a spikelet ... ... ... ... ... Eleusine. Point of the rachis of the spike naked, projecting. Dactyloctenium aegyptiacum. 26. Spikelets with 4 perfect floret, with or without 1 or more male or barren florets, or empty valves, below it... 27 Spikelets with 2 or more perfect florets or very rarely with only 1 perfect floret, which has male or barren florets or empty valves above iti tec iay clic.) TE 13 . Spikelets in pairs, usually-one sessile, the other pedi- celled, the latter sometimes rudimentary. Lower glume rigid and longer than the florets. (Trib. Andro- pogoneae):... ... : Spon 20) Spikelets either not in “pairs or if. in “pairs ‘then the lower glume not rigid and shorter than the florets ... 39 . Spikelets all alike or differing only in the lower glume 29 The two spikelets of each pair differing in sex and SISBHGE UIC ened toe Coane sicte h(a lan BEM eA Farge can, tS Bey 29. Racemes in a panicle Vos Shes ae SEL ME Lede SEE me Racemes 2 nate, digilate or fascicled — Fae RiGnes ot eae Soe 30. Spikelefs awned . Rand sedate hacen Sutepeeae ee _ Erianthus. Spikelets awnless . aaa 138 PS rsce sos ented 31. Panicle silky, spiciform. Rachis not fragile Be Oe Ont 37. 38. 39. 40. Imperata arundinacea. Panicle silky, much branched. Rachis fragile ... Saccharum munroanum. . The two spikelets of each pair alike in all respects. Pollinia. The two spikelets of each pair differing in the lower SPMIMNES 22. vot. oes vee eee se. [Schaemum. . Sessile eqileieig a in Ghallone Aine sari ek Tega tr Meare 2 sessile spikelets not sunk in hollows .:. ...)e5 ss, 4. 35 All the spikelets awnless Rottboellia compressa var. fasciculata. Pedicelled spikelets awned :.. ... Urelytrum squarrosum. 5). Lower floret of sessile spikelet always male . Ischaemum glaucostachyum. Boveretioret ofall spikelets empty i202). 20... 3.088 36 All the spikelets awnless ... ... .. Elionurus argenteus. Spikelets not all awnless ... ... . eR cee ONT 1-3 pairs of perfect and male silelelis erifiemind by a whorl of male or barren spikelets, and the whole sup- ported by a spathe ... ... ........ Anthistiria imberbis. No whorl of male or barren spikelets at the base ... 38 Sub-sessile spikelets awnless. Pedicelled awned. Digs pogon polymorphus. sessile spikelets awned:... ... ... ...'. . Andropogon. Blades transversely veined. Flow ers unisexual. Olyra latifolia. Blades not transversely veined . Loatmnetire, ap sseatts, 24" 40 Glumes © or very minute (Tribe Gryzede) 4 Sak te 4A Glumes 2 distinct, or rarely lower glume absent, and PERS CISMEL esr hee mas, setesome se erate eee ian wee, ae Al. Lee 43. 14 Two minute nerveless valves below the floret. Bush SASS. xesden sion . Potamophila prehensii.s. No empty valves. “Fruiting ‘valves ciliate.., Viel erass =2 Leersia hexandra. One or more empty valves or male florets below the FETS MONOby kaw sai ance Sve eel eosine es rae eRe ee pss oe eee A single, fertile floret only. No empty valves ... ... D6 Two empty valves (Sometimes minute), or 2 male or barren florets below the fertile floret ... ... A cet eee One empty valve or male floret below the fertile floret 16 . Lower (empty or male) valves awned dorsally. Awns kneed . eRerre: aout . Anthoxanthum. Valves awnless or awned from the lip. AW ns straight 45 45. Kmpty valves minute, enclosed by the glumes ... Phalaris. At least one of the empty valves larger than the fertile ... Ehrharta. 46. Glumes not falling with the spikelet (Tribe Arundinel- leae) ee MS Sas ak oe he ee ER Spikelets falling entire with ‘the. elumes “(Tribe PAMICCAC) ite oe. es oe! cael. meres deh Baarient AD 47. Spikelets in clusters of three, es Bee eee -Tristac hya. Spikelets solitary 2.2.0... BN PRG OS HEAT A tbe sch . Valves awned from the back near the middle (sometimes AWMIESS Mi Ala) ss 2e53es ones see ee ee ee tae.) 9G Valves awnless or awned. Awns if present terminal, o1 subterminal, below the tip, or from a sinus ... ... 98 Spikelets large or very large. Glumes rounded on the back 7-11 “nerved . peta ts Esher teins Vat AN CNA. Spikelets medium sized to small. ~ Glumes more or less keeleda: 4-3 ranely—t_ memved.-:../ 20 ease es. OT Oe 100. 101. 102. 106. 107. 108. 109. 110, 18 Florets 2. Valves shorter than the glumes ... ... Aira caryophyllea. Florets 3-6. Valves exserted from the glumes ... Avenastrum. . Styles distinctly lateral on a hairy 2-3 lobed appendage of the ovary. Spikelets rather large ... .... Bromus. No hairy 2-3 lobed appendages on the top of the ovary 99 . Valves 2 cleft or 2 lobed with or without an awn or MAUIETO ACO HAE PSUS eee a! cases. Poem eek ae a ae 100 Valve entire or minutely bitid, awned | or awnless ... 103 BVOC ES Ge eye Le oc URE wnat te ea toaseciee evo ae eens Se mane pee eee Oe EE Florets more than 2, uppermost often reduced ... ... 102 Top of the ovary ane Seed adnate to the thin PeLUGapre. Se ; Moonee 2 ae Pentaschistis. Top of the ovary hairy. ‘Seeds free except along the hilum inside the crustaceous pericarp ... Pentameris. Annual or subperennial. Uppermost of the 6-7 small florets exserted. Awn straight or O ... ... Schismus. Perennial, very rarely annual. Florets exceeded by the glumes or more or less equalling them. Awn kneed OTA TEGUCEd: (oO: ay MMUICTON Rs. ce) Sees ... Danthonia. ANTAL ENS CNV Gent irae Meath sh cen oy RFCM 6) ie a banca wee 104 Valves awnless (occasional spikelets i in Achneria setifolia BIRC MERWE CE ene aco tee atau eae eam anes uBleaWneey Lamy enen etme RTT) MeN ALVES Wi =O ICTEVOC! Jeon cel ates, co AO ces Mum cetne oles Gabe oy dat aaeetamel Obes Valves 5 nerved . eee eet Deke cue mene Spikelets srieesetle. ina ennples raceme or - false spike . Brachypodium. Spikelets in open or contracted panicles. (See also 108 roy 1X0 ls: 15) Ve reat Bes htc FL Pee eee a3 . Festuea. Glumes very unequal, lower eomneliie: obeoleie: Awn of-valve long ... ... ‘ .. Vulpia. Glumes not very unequal. ‘AW! n of valve short or reduced TO MNUGLO Sst. . vee dis! Vn ats, he Valves keeled and eae ainnie re iactylis glomerata. Valves not keeled, or if keeled, ther 1 Gres not ciliate... 108 Perennial. Panicle not spiciform ... ...... ... ... Festuea. Annual. Pani¢le spicitorm —...:.2 2.5 ACRES ENS al eS) Rachilla glabrous or almost so ... ” ‘Koeleria phleoides. Rachilla ciliate 2... 1.5 4.4, ae 22 Trisetum pumilum. Spikelets in lax panicles or racemes, generally nodding on long capillary pedicels. Valves broadly cordate- ovate, boat shaped . i oaa Vb astiec on nee ues een ee ERE Zclls Valves not broadly cordate- ovate, “Doat shaped, etc. 111 qth. 112. iT R7 19 Panicle dense and spiciform, or spicate... ... ... ... ... 112 Panicle loose, or contracted and rigid, but not dense and SPMCIEGHIN GG oe Rte. ce ate Cee aes eeeees ee 114 Glumes 1 ie the base rarely 3) nerved (See also 90 and os Pe aS eS eee: ae aac ised ... ... Achneria. Glumes i Al nerved . ieee ate: Spelt 3. Valves with acute hairs, not exserted from the elumes. Lasiochloa.. Valves usually with clavately tipped hairs, exserted from the glumes (See also 22) ... ... .. es. Brizopyrum. . Florets 2, not of not much exserted from the glumes. Panicle trichotomously divided. (See also 90 and 112). Achneria. Florets 2—many uppermost often reduced, exserted irom tWeveiMMeS: wets. 2: Bee etm Ascie eee eat cots LAO) Valves muticous or mucronulate, “with nerves usually distinct. Hilum of the seed linear. ties also 105 and 108) . rer Pee oud) .2 Festuca: Valves Re. or rarely Pcuie. ite nerves rather faint. Hilum of the seed punetiform. (TribevRoese). 22116 . Panicle with very stiff rigid two ranked branches. Outer side nerves of the valve much more distinct than the ETI OULGW QUE! hey eee ae ee . Scleropoa rigida. Panicle not stiff and rigid. “Valves - more or less equally iMoushnsonretimes tantly merved o..-... t6.-... s0033 LET Glumes and valves rounded on the back ... .... Atropis. Glumes and valves keeled. Florets often with a tuft of aOR U MED ASE wacctnc a Matas Mes ose ae Weems Inset ee eee Ole KEY TO THE SPECIES NOT INCLUDED ABOVE. (THE GENERA FOR CONVENIENCE ARE ARRANGED ALPHABETICALLY.) ACHNERIA., 1. Panicle very dense to compact; branches extremely Panicle trichotomous, loose; branchlets at least equal to UW ey Wale ley cee see Ale action ee ipa eee) (XS) . Panicle 1-24 in. long. Spikelets 14-12 lin. long ......: ... A. ecklonii. Panicle less than 1 inch long. Spikelets 11 lin. long. A. curvitolia. . Spikelets. 1-14 lin. long. Leaves not more than } inch long... : sey ih er sesluncls, gays Sevan omens, ee Cr OD hv: Spikelets larger. “Leaves FOMBOT ee A Cee een he . Glumes obtuse to sub-acute ... ... ... . fea nde nnaone Glumes very acute to acutely acuminate He rita 6 . Glumes sub-acute. Valves prominently 9-11 nerved. A. aurea. Glumes obtuse. Valves obscurely 5 nerved. A. capensis. . Valves much shorter than the glumes ... A. capillaris. Valves equalling the glumes or nearly so ... . 7 Jou! CGA ( . Culms many noded. Spikelets 13-12 lin. long. A. ampla. Culms few noded. Spikelets 2-34 lin. long ... ... ... 8 . Panicle small. Spikelets 2-24 lin. long. Blades setaceous. A. setifolia. Panicle 4-6 inches. Spikelets 23-3 lin. long. Blades not S@LACE OMSL vince) Les JG ongecohede’ wae nas APSE teeny Ae URREC SEERA AGROSTIS. de SpUelets, dads Vim). Omen cet callin secteses Set cae) (sear) eee Sprkeletsrab-2)) lim Ome t55 5 es eye neta, che rks No agen eam 2. Spikelets 4 lin. long. Glumes obtuse. Panicle dense. A. griquensis. . Spikelets #4 lin. long. Glumes acute. Panicle lax. A. bergiana. . 3. Spikelets 14 lin. long . wae c useless Ae Sehlechteri: Spikelets about 24 lin. Jong . Ne VE MEK iG rss SURAT aL 4. Panicle, spike-like, lobed . eV Aes Ae DAEALENSIS: Pamelor laxiec. foc 2 eiaicks aha ee eee oN Coe ona 5. Panicle about 6 inches long sae waiidehwewtlece 2A DAF DUIgEna. Panicle about 11 inches or more long ... ... ... A. suavis... ANDROPOGON. 1. Annual. oe Corn and its varieties) ... A. sorghum. Perennial . SEER ac eae Ab eh 2 aie Sed Le eee eres Meee vo i) | +i Je) 10. oe 13. mEanicle large, ‘effuse, ‘nodding. Racemes numerous, all long pedicelled (similar to A. sorghum but perennial). A. halepensis var. effusus. Panicle smaller, not effuse and nodding, or if effuse then RACEINES LEME Il) MulMmMOem aides Maller. scsscss se: Ri . Racemes solitary ... ... ... SEE I Mage. Petes 8 Leyes a & A Racemes not solitary ... ... oa 6 . Lowest 2-6 pairs of spikelets male and “‘awnless. Upper sessile spikelets awned ... ... ...... ... ... A. contortus. Lower sessile spikelets not differing from the upper . Racemes 7-8 lin. long. Joints of the rachis filiform. A. ceresiaeformis. Racemes 2-5 inches long. Joints of the rachis stout A. hirtiflorus. Racemes silvery plumose, with hairs 5 lin. long A. eucomus. pocoes ae to silvery villous. Hairs never 5 lin. lad : Racemes digitate, fascicled, or panicled, but not 2 Palen iets ee kee Ae eel) I INE ae we ene ge ay Sr MI Racemes 2 nate. terminal on the culms or on numerous ISR AL CIAO tetens Wid nd ROG Le el I ae i Lateral racemes sessile . PUT ost Ce elt } Racemes peduncled . Rm ce ent me Sates orcas its Semel) Lower glumes oeaie flattened. Thesis, broadly winged BHOVED 22068 52: ee, 2 Aco distachyus: Lower glumes dors ally | concave. Keels not winged. A. appendiculatus. Racemes 1 articulate (i.e. reduced to 1 sessile perfect and 2 pedicelled, male or barren spikelets) ... ... ... A. monticola var. trinii. RaGeMeS MOn WarliCMlate ... ...0.5.cee eee cro seeiae cee wes, Sessile spikelets alike in form, but differing in sex (Western spec) ... ... solgpe ns eee A SOILS TIS - Sessile spikelets alike in ‘form ‘and SOiKie ce teh emer Alice . Lower racemes shorter than the common rachis. Glumes pitted... us. a... A. intermedius var. punctatus. Lower racemes ‘longer than the common rachis ... ... 13 Lower glumes of the sessile spikelets not pitted ... A. ischaemum var. radicans. Lower glumes of the sessile spikelets pitted. A. pertusus. 16. ily a0: 22 Racemes 2-9 inches~long, on the main culms ... ... 415 Racemes 4-45 inches long, on branches of a panicle 19 Lower glumes gases flattened. Keels broadly winged 31) OXON Sage an eee Say sue ot actos A. distac hyus. Lower glume with a narrow groove. Keels not winged 16 Blades very narrow, filiform ... ... ... ... ... A. filifolius. Blades linear 1-5 tins broad s.4 2... ¢ : Pasar Bees St on Blades rounded or sub-cordate, and sub- -amplexicaul at tte MbaSe Mew te eee eee i¥ oes aasy Sh. ae A eI plectens. Blages narrow. at theibase... ee) acces Saale mee eee ane Culms simple. Blades 1-2 lin. broad . Peli ae A. schirensis var. angustifolia. Culms branched. Blades 2-34 lin. broad ... A. sehinzii. Column of the awn glabrous ... .... bel sheh erect ee Column of the awn pubescent or hirsute oh, ed es wee Leaf sheaths quite glabrous. Lower glume of sessile spikelets with a narrow groove from the middle down- UTS hs see odes Bea wake awe edes sepia es SEE CUES 5 Lower sheaths firm, ‘fugaciously hairy to tomentose at the base. Lower glume of the sessile spikelets flattened or con- CAVES eas hses Ae Ree ON RSET Keels of lower elume winged above ne A. nardus var. marginatus. Keels of lower glume rounded. Secarcely winged A. plurinodis. Callus of the sessile spikelets very short or obscure, ODES. co Bie: No ory tr de eee | ieee Callus of the aeaeiito spikelets acute, “up to 1 lin. long, densely bearded ... ... ... ede: ae Oe eee) Spathes broadly lanceolate to ovate, \-1 inch long ... A. eymbarius. Spathes narrow linear to lanceolate, 1-3 inches long... 24 Spikelets of the lowest 2 pairs of peduncled racemes alike La OTM sain SEN a5 sue shee A. buchanani. Spikelets of the lowest pair of ‘the peduncled raceme of GitteRent “SOK... 7 Nhe Tee Ae scanner se Racemes short, 2-5 jointed ... ... Tete Satie pam dichroos. RacemesHong.b-Umany jombed 4 eri 5-2 eyes eee, Spikelets silverv villous ... ... tee es Re 48: ae aee th weal Spikelets not silvery villous ... ... . 28 Tall stout culms. Common peduncles laterally exserted. A. auetus. Slender culms. Common peduncles equalling or exceed- ing the spathes!0 y.50 eo aie eee LS 20 28. Culms rather slender. Panicle narrow. Common peduncles curved)... .....0 0.002... i... dregeanus- Culms stout. Panicle decompound. Common peduncles. MO MSOeSMOMla hye ‘CLEVE: 22. ee rat ae, Mme: cee ees? Soe! ee) 29. Common peduncles enclosed or laterally exserted. Hairs MA PrESEMy WHIGISIE 2.2) 4215) eciececessa se ewes SCMLMperi. Common peduncles usually long exserted. Hairs if MRC SEM MUOU Sen echo o sd)... see nae ney tesiece oe PUES. 30. Hermaphrodite spikelets subtended by a bract-like appendage PRB esesouenet ene, Veo RLS ... ... A. ruprechti. No searious bract-like appendage APR Te COS J ioe ate bhai mee | 31. Racemes 5-6 lin. long, each with 4 hermaphrodite SPUN CHEE eases oe 6. .... . A. filipendulus. Racemes 6-12 lin. long, wilh more than 4 hermaphrodite SOUEIET or. baa: Oe a oe ee Dee at) tact Ae Pe ee US 32. Culms simple. Racemes 6-8 lin. long : ue transvaalensis.. Culms branched all along. Racemes ‘about { inch long. A. pleiarthron. ANTHEPTIORA. Perennial. Involucral glume minutely tubercled and villous outside. Lower valve 5-7 nerved A, pubescens. Annual. Involucral glume glabrous except at the base. Lower valve 3 nerved ... ... ... ... ... A. undulatifolia.. ANTHONANTHUM. {. Panicle small or reduced to a scanty raceme. Culms and KeaRge swt viewT Simei Weak o.. .c oe ae Ba A. tongo. Panicle spike-like. Culms erect, 1-3 feet long an ok Mile: 2. Spikelets pallid, 4 lin. long. Lower glume 1 nerved A. ecklonii.. Spikelets greener, 3 lin. long. Lower glume 3 nerved ... A. dregeanum.. ARISTIDA. Powws, wlabrous.; s~Glumes 4: nerved: =. %..-. 2: All or only the middle bristle of the awns plumose. GoM Siro METVC Oe t.1i7s (cms coterie Wee Ree vento ae ACE 2. Awns disarticulating from the valve, distinctly stipi- UEP (ag RO a en 2 oe Awns: not disarticulating, but ‘sometimes jointed just below the branching point ;.. ... ... ... EKG 3. Glumes aristulate. Foot of the ¢ awn 3. 20 ity ante kth A. sieberiana. Glumes not aristulate. Foot of the awn 1-6 lin. long 4 or +] 10. iil 13. 16. 24 . Ligule a line of very short hairs. Panicle 3-6 ins. long. Lower branches 44-3 ins. long. Foot of the awn 1-23 ima Lome sate. peat Mere" crancpes, beet ate Ave, VESUIUAs Ligule. a woolly fringe. Panicle 6-18 ins. long. Lower branches 4-8 ins. long. Foot of the awn 24-6 lin. long. nt Sind stan dS gids once aD . Glumes sub- ~equal: foot of the awh 1 24 lin. long ... A. spectabilis. Glumes very unequal; foot of the awn 23-6 lin. long ... A. stipoides. Awns articulate with the valve just below the branching point, bub not deciduous: 5 5.2; Hae -saeentteal =e Awns perfectly continuous with the valve SSPaatae, ote ieee) . Sheaths. naked at the mouth ... ... ... ... A. congesta. Sheaths bearded at the mouth ... ... ... A. barbicollis. . Annual. Valve not beaked. Anthers $ lin. long ... : A. adscensionis. Perennial. Valve narrowed into a beak. Anthers 4-3 lin. MGT tee Uc OS te aie tonel teas "Bite een alae Pete toa Seen ae . Paniclesopen,, lax: branches 3-6, mn lone ets ccmce. seen Panicle narrow, contracted, often spike-like ... ... ... ill Blades 8-412 in. long. rae 5-6 lin. ae Awns up Oey LOM Te. . A. burkei. Blades 1-4 in. long. Spikelets 3-4 lin. long. “Awns 4 lin. Omen ceeye : tans . A. bipartita. Culms woolly holo ihe ‘pads. Bane rer feet long. A. sciurus. Culms glabrous. Panicle. 2-6) 1. lomeg.-20..-os-ree) oon ee . Glumes sub-equal, shortly mucronate ... A. aequiglumis. Glumes unequal . omer s : ae oe ee! |) Culms terete. Spikelets 5-6 ifm none. “Valves exserted. A. angustata. Culms compressed below. Spikelets 34-4} lin. Jong. Valves not exserted. Glumes aristulate A. junciformis. Awn continuous with the valve. Whole plant hairy. A. sericans. Awn disarticulating . aes: abl eatin om, ecten em allay . Valve gradually passing ints ‘the AW scene eee el Valve minutely and obtusely 2 lobed. Awn from the SUMMIS: 2 Meee: RRB. Mes? ote. SD Glumes emarginate. Sheaths long ‘bearded at the mouth. A. ciliata. Glumes acuminate. Tips minutely truncate, convolute 17 sep 18. / 20 Side bristles of the awn sparingly ciliate ... A. lutescense Ally tie: bristles: of ithe awn) plumiose)-.....2. 60 22... 148 Awn tardily disarticulating with the tip of the valve. A. capensis. Awn readily deciduous with the upper half of the WICH WSU NE Oi ce yt eA RPE rs cher We penta vinttee Se RC) 19. Suffrutescent. Uae 6-7 lin. long. “Middle bristle 9-42 TOMS Sec san. venee . A. namaquensis. Not suffrutescent. “Spikelets up to a lin. long. Middle FOG Om se Hee tei, NOM yar aat cht cee nee Sees ta ia proxima. 20. Lower glume rather longer than the upper ... ... ... ad ower giumeshorter than the: upper... <4... =. (22 21. Annual, about 1 in. high. Panicles 4 in. long ... A. subacaulis. Perennial, 38-42 in. high. Panicles 1-6 in. long. A. obtusa. 22. Pamcter narrow, rather lax, mot spike-like ... ..: .. 23 PE AME MS PNNO= NCE vee secede SN EN LL NP oe deta cal uileoee 23. Culms 14-2 ft. 4 noded. Awn plumose from below branching point .. Math ccete sad sate A. uniplumis. Culms 4 ft. 1 noded. “Middle awn plumose in the upper iNET ee aay nee moar TA mepatey san sean en OTEGeana: 24. Culms up to 4 ft. panier: nee cts, Sets A. geminifolia. Suffrutescent. Panicle glabrous ... ... ... A. Dbrevifolia. ATROPIS. Leaves 1-4$ lin. broad when expanded. Panicles ovate to subdeltoid with rather coarse and stiff spreading LONGING Sivan oven ane canto oe re ate nse eee ae DOL EERE Leaves up to # lin. broad. “Panic le linear, with erect finely filiform to capillary branches ... A. angusta. AVENA. 1. Valves glabrous or hairy at the base only. Rachilla tough or tardily disarticulating ... ... A. sativa. Valves hairy to or beyond the middle. ‘Rachilla readily GiSamibie ulate a ces Gack, Rhee cy eal on BS aes Anette a2 2. Spikelets 15-20 lin. long. Rachilla as between the WaUINE Sime se nia: ‘ A. sterilis. Spikelets 9-414 lin. tong. ~ Rachilla. ‘villous “between the MANIVES) rafatite we UREN epee Mee eet SUA Me gia irae one e ae et 3. Valves shortly pind. : .. ... A. fatua. Valve lobes produced into ‘Jong bristles ... A. barbata. 26 AVENASTRUM. 1. Spikelets 6-9 lin. long. MRachilla joints 14-2 lin. long, Spikelets 33-6 lin. long. Rachilla joints $-1 lin. long 4 2. Spikelets 2-3 flowered, as long as, or slightly longer than hve: oes We oe. . .. A. quinquesetuni. Spikelets 3-4 llowered, ‘much longer than the glumes 3 3. Panicle 6-9 in. long. Leaves long, faced a A. longum. Panicle 2-3 in. long. Leaves mostly basal, short, sub- 1/31/20 6 Rees eee ¥ ven woh, gee) eet as, A Oregeaminin. 4. Spikelets rather compact, ‘slightly turgid. Valves imbri- CALC is sj eae nab- enaliees toanh isu temater cocci yee )ekle CULE MONEE LUNES Spikelets looser. Vaives not imbricate, spreading, ANA ETOW oS ate Seema beh wee ata ate Meee alg eaten D 5. Panicle flexuous. Rachilla long, hairy. Valves ‘thin, STMOOUM .<,, dak tees cee) Cee maces oa cena eee: Geng eee Meaee Ne Rd Panicle narrow, branches adpressed. Valves sub-carti- laginous, below the awn, scaberulous or granulate — 6 6. Blades 9-20 in. by 2-24 lin. uae a 5-6 lin. long. Rachilla lone hairy... <5 222 se0 seeses = . A. dodii- Blades 2-9 in., very narrow. Spikelets 31-5 -5S lin. Rachilla slabrous0r- shortly Many ac. ca...) eee A. antarticum. BRACHYPODIUM. 4. Annual. Anthers. 4-3 IN OMG aes esses Lucan Pereomial Anthers 44-2 lim. Wome. asn cas saa seen eet Ps 2. Culms leafy for more than half their length on B. flexum. beaves, crowded al tne base: <4 sapees easter -ee B. bolusii. BRIZA. Spikeletsus-8" lin. lene. ic wo we os ae oe Be maxima Spikelets: 4-2 lime Tome ee 2 eel.) ses een) aoe acs ee BRIZOPYRUM. 4. Spikelets in 2 ranked spikes or the lower clustered 2 Spikelets in spike-like panicles all round the axis... 4 2. Glumes and valves subcoriaceous, very obscurely nerved. Hheawes Wig Lo os ee. eseumes don con toe Sache ed Pe MSE. Glumes and valves thinner. Nerves prominent in upper Daties sheaves glaucous, Motegi s:, cheese 3. Spikelets loosely imbricate, 34-4 lin. long. Leaves.long, flaccid .2%s.. Aree . B. alternans. Spikelets tightly imbricate, 2 2- 24 Ii - long. Leaves short. B. brachystachyum. ais Or 27 . Spikelets 2-2} lin. long. Valves with clavate tipped cilia. B. acutiflorum. Spikelets 14-2 lin. ae Valves with acute cilia or bristles! es023 4 «: es OO Go Se nae) Ske eee een. . Spikelets finely hirsute all. over. “Glumes with bristles. B. ciliare. Leaves glabrous (except at the mouth). Glumes Clg DvOUS: ss. se.c : Bt drcrralc emai eine AO . Uppermost sheath usually ‘exceeding base of panicle. B. obliterum. Uppermost sheath remote from the panicle ... ... B. glomeratum. BROMUS. A: 4, on Glumes and valves strongly compressed, acutely keeled. Valve about 13-nerved ...... ... ... ... ... B. unioloides. Glumes and valves not bcth strongly c ee and keeled. Valves fewer than 413 nerved . peiatatis 2 . Valves 1 in. long. Lower glume 7-10 lin. ‘Upper elume AA Ae Ns AWN, 2225) UM. ck obs ons ese B. maximus. Valves Jess than # in. long. Lower elume Jess than 7 lin. long. Upper ant less than 8 lin. long. Awn much SORLCT) 2. 2). 4c. 0G. ainvoluerats: Blades glabrous below. All the valves with a kneed Qwihl 40-1 MMs LOM Se? a5 ae Sette ahs: Caria at ake een 2. Culms erect, blades 2-5 in. long. Lowest valve without Side bristles: .:2 hin. aisctepedet seen cone een eos Cum LeQeamas. Culms ascending. Blades 6-10 in. long. All the valves with side bristles. 23... c3. es denice, «as aos (Ge SEMAGeTE: CHLORIS. 1. Upper glume very broad, shortly bilobed, mucronate. Valvesumrucronate 2. ¢.2), 205. 1eieae- eet ee ed Glumes narrow, acute or mucronate, keeled. Valves QI TICO! 2.5, ese iacl aoa ton (As Sa oR eae Reged en ae 2. Awns as long as the valve or a little longer ... C. gayana. Awns 3-6 times the length of the valve ... ... ... ... 3 3. Rudimentary floret minute, on a long rachilla joint. C. pycnothrix. Rudimentary floret more than 4 the length of the fertile floret, on a rather short rachilla joint ... C. virgata. CYNODON. Culms many noded, with leaves mostly crowded at the base. Ligule a ciliate rim. Rachilla produced ... C. dactylon. Culms 2-3 noded. Ligule membranous. Rachilla not PLOCMCEd <.. reel... ans ad diecast aaaiee ee oe COM DLE mise DANTHONIA. fi. ‘Spikelets45-2 imehes Wome: | 6 cy nn eee ey eee eer cae z Spikelets 44ne¢h-0r lessee 0is seeding 2 ee. plle eee ie eames 2. Blades 6-12 inches long, filiform, tapering to a long setaceous- point ... ... ... Sooo 2s DD. amaerantha: Blades 2-3 inches long, linear; tips filiform, obtuse. D. brachyphylla. fay ot 6. ~) 10. id 13. 16. 29 . Lower sheaths more or less covered with a coat of wool. Panicles usually capitate... ... ... ... Rein Scat see Lower sheaths glabrous, or minutely “pubescent or tomentose. Panicles not capitate ... ... ... reba iT . Panicle loosely contracted ... ... ... ... ... D. zevheriana. Banicle, conipact spike-hke or capitate’... .25 2... 2.5 dD . Spikelets 10-12 lin. long in large heads 2-2) in. long. D. macrocephala. Spicelets smaller, 4-84 lin: 1OMG, s. n ee cee ame ee tne 6 Spikelets 6-83 lin. long. Glumes narrow, long and acutely acuminate ... ... ... we . D. lanata. Spikelets 4-7 lin. long. Glumes. rather ‘broad, shortly acuMinabesor mucronate .....--....%.. .. D. lupulina. : Spikelets awnless, or awn reduced to a mucro...... 8 Smusclets. dishimetiv awnede nw ack seek aceessens wes cease . Spikelets 2 lin. long. Awn reduced fe a mucro from a SIMUIS:. sot ee roe os we : : Seah pace ae ... D. inermis. Spikelets turgid, 4-6 hie eae prunes ... D. decumbens. . Dwarf plants. Blades not exceeding 2 inches. Culms se EINOCE l.co: we. onde ace SPA cre Co ae iy. oak ecm en) Mon GUNN elitr atenht Wolke dramaacuhiccen ane ya i ape nin’ osc aeRee mene rene! PLO Valve lobes Caniice! 1D AMG OV epee nee elias eee ee Valve lobes mucronate, or long setaceously acuminate 12 Perenmial. - Valve: lobes ciltate ... 02. 20: ... D. purpurea. Annual. Valve lobes truncate, not ciliate ... D. tenella. Spikelets 5-6 lin. long. Valve lobes mucronate D. pumila. Spikelets 2-23 lin. long. Valve lobes long, setaceously CUMMINS Ca50 we aes ads tas Vee PE PMA ey Ee D. curva. Spikelets 2-45 lin. long... s2. lat os ete 14 Spikelets about 6 lin. (rarely to 10 Tin.) long. Rather COMESECOLASSES wast sees anohons ales, Sehmbewe see. ay oo eee LO Spikelets 2-24 lin. long. Valve ee leie: setaceously OMUMUTIALC: 2. ! ca ent 34ers wood see hee : . D. curva. Spikelets 34-43 lin. long. Valve ‘lobes not ‘setaceously ACUMINATE 2... 26: Pee ence es ae SIRES ars Aer ere eae ema! CD Suffrutescent. Lower sheaths coriaceous D. suffrutescens. Herbaceous. Lower sheaths thin... ...... ... D. glauca. Inflorescence a distichous linear spike ... ... D. disticha. Inflorescence aotrue: contracted panicle: x... .2¢...., -.2. 17 Vi. 18. 19. 30 Valves loosely villous, hairs not in tufts. Lower sheaths pubescent or tomentose and pruinose, but not covered with a coat of wool ... ... ... ...... ... D. elephantina. Valves with distinct tufts of hairs. Sheaths glabrous except sometimes near the mouth or at the very Das@ ise den ac ah Nehsfe; store Testo. lis texcamalerseeerete Leese 18 Sheaths woolly at one “inven lTns: Hair ies. on valve 3 on each side at the base of the lobes, and equal to them. D. papposa. Sheaths glabrous or almost so. Valve tufts of hairs forming a dense straight transverse fringe alt or near its middle, or in an oblique transverse fringe near the’ base, or submarginal on each side =. 2... 19 Culms and leaves very robust. Tufts of hairs a trans- verse fringe at or near the middle of the body of the VieIVIe en eee 5 ics aoetad. Gee DENCHNeEA Culms and leaves 1 more ‘slender, “firm. aki of hairs SUb=MareiinalOr (basal nels, aes 1 eae bok. ener 20 20. Glumes 1 or lower sub- 3 ened Tufts of ian in an oblique fringe near the base of valve. Lobes of valve almost wholly adnate to the awn ... ... D. macowani. Glumes 5-3 nerved. Valve tufts of hairs submarginal; lobes: free from: therawim: \. cue. eee aie chk en 21. Blades wirv. Lobes of the valve mucronate ... D. dura. Blades filiform. Lobes of the value acute, with a slender SIME AD PISUEN a ose gence aaa eee ae “as wee. DY Strietas DIGITARIA. 1. Racemes rather lax, compound near the base, villous with long silky, often ee hairs, conniving into a brush-like point . st ivesttas RE at vated GeteAtexe tie ee oe Racemes simple or nearly so. Spikelets glabrous or covered with fine adpressed hairs... ....... ... ... 3 2. Racemes sessile or subsessile, sub-digitate ... D. tricholaenoides. Xacemes peduncled, in a_ scantily branched panicle. D. flaccida. 3. Racemes setose. Spikelets surrounded by stiff hairs from tips of the pedicels ... ... ... ... ... D. diagonalis. RACeMeS NOL SClOSE (ae came ree ee CES ae eo 4 4. Racemes solitary, dense, densely villous D. monodactylon. Racemes:i2/ to may iss. 06, eas Ss ete ages eee ol . Spikelets quite glabrous ...... ............ D. diversinervis. Spikelets not quite glabrous ... ... 6 6. Racemes continguous, often resembling a solitary raceme. D. argyrograpta. Racemes never contiguous except in a very young 7 ot state ... rea oe nl cocina alae orphrae het « 7. Perennial . BE 38 eG eed a> INR Se hors DLR ee Annual . EAP ee RS ee 8) 8. Culms rather “stout ee ft. “Blades 4-1 ft. by 12 lin. D. eriantha. Culms slender 3-1 ft. Blades setaceous, 2-6 in. long. D. setifolia. om edi¢els: terete: smooth t205..55; 2.22... D; tenuiflora. Pedicels angular, scabrid~.. ..... eet AO) 10. Pedicels shortly hairy near - the tips. " Spikelets obtuse, silky with clavate tipped hairs in very slender long RaCeMle Srv ect. Asiaag ieee D. ternata. Pedicels glabrous. Hairs of spikelets not clavate Boe a) 11. Upper glume long acuminate, exceeding the upper valve. D. debilis. Upper glume shorter than the upper valve ............ 12 12: Spikelets 3-1 lin. long. Lower ee OF Valves closely nerved . es . D. horizontalis. Spikelets 1- ik ‘lin. ‘long. ‘Lower “glumes usually distinct. Inner lateral nerves of the lower valve rather distant irom the middle: merve..) <2. 4... ... D. sanguinalis. cee ACHNE. . Blades 4-2 in. long, very rigid, pungent ... D. paucinervis. Blades 3-9 in. long, flaccid or sub- -Tigid, never pungent 2 2. Spikelets 2-3 flowered, reddish. Valves shortly awned. D. biflora. Spikelets 5-10 flowered, ae green. Valves awnless or mucronulate:... ... .. Een A Me See? ete ences tee 3. Blades more or less flaccid. Ligules very short. Valves ODUUSE An ce: .. .. .. D. eleusine. Blades more or less ‘Tigid. “ Ligules up to *2 lin. long. Valves minutely emarginate .:..:. .. ... ... D. fusea. EHRHARTA. 1. Empty valves subulate -caudate, similar in outline, equal or unequal, 2-4 times the length of the glumes... 2 Kmpty valves not subulate-caudate, less than twice the length of the glumes, or if subulate-caudate then the culm is bulbous at the base, or the empty valves are WET VCISSMMM LATS ere.’ SAP cet gcle OMA Se SL esol aS tees DD 4, Or ~i 9. 10. ak. 13. 32 . Flaccid annuals. Lower empty valve exceeding the RET UELG cars cach cneheen. vec cet eee eee ears cele ok Seca ee Me Perennials with crowded basal leaves. Lower empty valve: shorter than fhe feriley..-.: jest fee cee ee Fertile valve 1-14 lin. long, Serge or slightly exceed- ing the erueee RES 38 BR . E. triandra. Fertile valve 23-23 lin. lone, much exc eeding the glumes. SUGMIEMS Ges 65 suo hegttgretesees ce ecne ero nce merweet bar longiilora. Leaves 2-5 lim. broad, swhen Mat 2.3. ne we. nc nes Ue ae heaves: flimorm: iss. cas Sacdes (not ies ..we ete eee ke COIR. . Culms bulbous at the base, simple, 2-3 noded. Empty valves sub-equal . Bae 6 Culms not bulbous or if sub- bulbous then branched, 1-6 noded, or eniply valves mmequal: 2-2. a eae Lower empty valve almost equally wide throughout. Blades usually convolute, rigid ... ... ... E. longiiolia. Lower empty valve widening above the middle, or like the upper coarsely rugose. Blades usually flat, WOa Cee eee nied. ais Ne ne OEE: aes ie eae opikelets 3 Tim. lOmMe: se 20. ose caraets een eget ee Sore Spikelets 4-6 lin. long .:. ... ... sets tbas Neek! be tke CAETISISs . Lower empty valve less than 4 length of the upper, differing from at. tn substance a= svete ee Kmpty valves similar, or lower, shorter and narrower but Alike Upper aysubstanCe senses coe okey eee Culm coarse, almost woody, below. Blades very rigid 10 Culms and ree ne. Lowery Tine, +. eae (ene nent Glumes about 4 the length of the spikelet . E. rupestris. Glumes 3-3 the length of the spikelet ... ... E. setacea. Glumes equalling the spikelet ... ... ... ... E. uniflora. Glumes scarcely 4 the length of the spikelet ... ... 12 Spikelets in 2-9 spiculate racemes ... ... E. tricostata. Spikelets ‘Solitary =. es .c2-d-c-t0-> qo ee eae ee se Uae CO Spikelets 4$-74 lin. long. Upper empty valve not hinged by an Appendae torte tertile tiers ee. oe eeae 14 Spikelets 1-24 lin. long or if up to 4 lin. long, then upper empty valve hinged to the fertile, by an ear shaped appendage: ona “‘pivoh like “knob civic. ie -on eee: oO . Lower nodes reversedly hairy. Keels of empty valves long hairy: sk os. ase . E. barbinodis. Nodes glabrous. Emply valves hairy ‘all OVER oxo Asset 33 15. Innovation buds or young stolons covered with villous SCE EG) AGU AIS TeTHe0) pireie enc. Sehr ieee eneeeee E. gigantea. Innovation buds with only basal scales fugaciously tomentose. Culms ae from a decumbent and ROotNe base —:.5 24) Nittseeaes: te Be Villosas 16. Spikelets 1-12 lin. long or if “fp fo : 24 lin. (EK. erecta), then the upper emply valve with a pair of obscure beard- less ridges, and no definite appendages at the base 47 Spikelets 2-4 lin. long. Upper empty and fertile valves hineed tozether .:.--.... Bhat ee iiee SO 17. Empty valves very similar and sub- “ital, “exserted from Per ATC Sietes sere ech Sora c cee ee Vaasa ine ee Bh: se 18 Upper empty valve about equall ing the | glumes. Lower 4 LeU Olt CEU POEL evs tine cetead steed cose eonseca. 19 18. Perennial. Spikelets 13-23 lin. long. Stamens 6. E. erecta. Annual. Spikelets 4 lin. long. Stamens 3. E. delicatula. 19. Perennial with basal tufts of villous leaves. Valves Stal COMUS ssayest Sie hk) weg oe MElCOIMES: Annual. Empty valves hairy 665 aaeee os I. bnevitolia. 20. Suffrutescent. Blades very much reduced or sup- PRESSE Gan rraa eM e ey ters bai sch et os 6 on 2 Naan Moe Oa Not suffrutescent. Blades flat-or convolute ...... ... 22 21. Culms stout, usually bladeless. Glumes usually shorter than the valves’ :2.°.3. <:. Ser eked wee) cape es DAMLOS A: Culms slender, sometimes bearing short blades. Glumes slightly exceeding thepvaliviest g's... .6s es aphylla. BomUMIDEYS VALVES: ClO DFOUS [.ciis.b tee. Sen Ssh. desaeka weveile vane oO PAA VRVATVIES cIMGMEVa is. 6 tras sceeeiees, aeeeias © Sache aes ee ee 23. Spikelets erect, 3-4 lin. long. Panicle spike-like ... E. subspicata. Spikelets nodding on the flexuous rachis of a raceme, Ceo LOMB Te. ceca to ences new 5 PORATION. 24. Annual. Culms $-1 ft., 2-3 moded oss. %. He spusilla: Perennial. Culms 1-2 ft. te O NOCH) Te. ha. E. calycina. ELEUSINE. Spikes slender: =Valves-acule?.2, 20.22 ais: E. indica. Spikes thick, often curved. Valves obtuse ... E. coracana. ENNEAPOGON. 4. Awns scaberulous along the margins ... ... E. seaber. Awns-distinetly plumose or ciliate .2..... 0.0 00.0. lee = 2 ap 34 Almost glabrous. Culms very wiry, 4-2 ft. long ... E. scoparius. All parts softly seamen a cae Nodes villous. Culms not wiry . 3 3. Culms 2-6 inches long. “Side nerves of elume evanescent above 0.. 35 . ... E. brachystachyus. Culms 1-3 ft. long. “Two side - nerves of the upper glume MELCUPPEME ts. isn aeatees «eats teat coc oseace ale SEMOIIES: ERAGROSTIS. 1: Valves ‘or pales: Jong GUulkate’ c..7 2006.00 Gon coe ae.b tee Neca ee Valves and pales not long ciliate ... ... ... 3 2. Perennial. Both valves and pales ciliate ... ... _E. ‘Jappula. Annual. Pales ciliate. Valves not ciliate except some- times at the base of the keel... ... ... ... E. ciliaris. 3. Spikelets small, breaking up into false fruits consisting of the grain enclosed by its valve and pale... ... 4 Spikelets ee ee up but not into false PYUMUES: Sect nese ei he Tat Bortoekts th. ‘by 2 8 lin. ae Culms very slender ascending from a ae or rambling base many noded, often branched. Leaves 4-3 IHU! BY GS ala AA ae POEM SS te a ee ere Culms slender, compactly caespitose, or Sie decumbent at the base then rather stout. Leaves usually 3-5 TCLS Se EI Sha tak ee, chee ark et a A eee WEIS AVCULVC 1-9 DOK VCOsiton. oes haieen aces tbat Sewlaen sed Vanee ee MGNRVer VAlVe dre ME EVE .. ieee teas casce soesceee as P29, Lower branches of panicle 3-6 in. long. Pedicels 4-14 ins. long . : Revere Rae Pol >. perlaxum. Lower branches ‘of panicle re) ins. long. Seen 3-1 LL pet CG) 0 ater tee ere Dee acer omer tes eee eee, Spikelets qe to Acura aie: often pubescent P. aequinerve. Spikelets obtuse, glabrous ....... ... enantio | wort Leaves glabrous. Lower glume flote more “than 4 length GieSpiLKeles, 2.275 aks ss. tee e- nLCulme: Leaves finely hairy. Lower elume x length of spikelet. P. hy meniochilum. 25. Panicle large effuse. Spikelets 4 lin. long. P. laticomum. Ramiele scanty. spikelets 14-2: lin, lomg 2... 2.2 22 26 3. Blades shortly ee ee pedicels up to 44 lin. ROD pees aos eer csr chusqueoides. Blades not petioled. ‘Longer. pedicels up to 4 lin. long. P. obumbraium. . Glumes and lower valve 3-5 toothed ... ... P. ecklonii. Ginmes and lower valve entire 2 3.4 .a-s. se ets 28 28. Culms 4-many noded, from a creeping rhizome or reap decumbent, branched IQeNS[OM ase Gene ke 29 Culms 1-3 ‘rarely 4) noded, simple; densely ‘caespitose 30 Stoloniferous. Lower leaves distichously imbricate, 13-3 lin. broad, usually rigid and involute ... ... P. repens. Not stoloniferous. Leaves more distinct, broader, flat, Palmers (aACEIE oc «cesses. Gaoree aso ve J. coloratum. 42 ~ 30. Glumes and lower valve equal, very similar, 5 nerved. P. natalense. Lower glume smaller. ee re i. Merved Ls 4. sot aL: TOWer Walveso MelVed) os) sere Gi ieeA seta. cence eee P. minus. Lower valve 5 nerved . ja deteteek a teiyege eae Mee UCR CARRIE. 32. Spikelets obtuse or sub- obtuse ered koa Wek ae ata taney eee Spikelets distinctly acute or acuminate Ses Oi aces Seen S3- Spikelets 2:5 Line lone DuUneidae, oko. sete Spikelets 4-14 lin. Jong, not turgid DNS He uaa dhe ake meee Oe! 34. Tips of glumes and lower valve callous. Lower valve Fy ORVEC Ck, tenttarvrincaeene ge ckinee kc eioce P. zizanioides. Tips of glumes and lower valve ‘not callous. Lower valve inerved ys Sieh ..... P. deustum. 3o. Perennial. Lower valve 5 D nerved. ‘Upper finely wrinkled. P. maximum. Annual. Lower valve 7-9 nerved. Upper quite smooth. P. laevifolium. 36. Pedicels very short. Spikelets glaucous. Glume and valve faintly 5 nerved ................-..P.-meyerlanum: Pedicels 2-6 lin. long. Spikelets not glaucous. Glume and. valve distinctly 5-13 merved=: 2... :-s2-e-s-eon 37. Spikelets acute. Upper glume 11-13 nerved ... P. miliare. Spikelets acuminate. Upper glume 5-9 nerved ... ... 38 38. Longer pedicels up to 24 lin. long ... ... P. proliferum. Longer pedicels up to 6 lin. long... ... ... P. capillare. PASPALUM. iF Culms usually erect. Spikelets obtuse or sub-obtuse. P. scrobiculatum. Culms ascending from a ee base. Spikelets SUGAT EC psf <2 ct 03.52 gh SaaS Ie AA eae ec ee eee te oe Z . Lateral false spikes sessile. or “subsessile A ae digitaria. False spike peduncled 2.2 sie: tq. aisiiehum: PENNISETUM. 1. Involucre reduced to a solitary bristle ... P. unisetum. Involucre not reduced to 1 bristle ... ... ... Rey 2. Annual. Tall stout plant. Involucre peduncled . P. typhoideum. Perennial, not stout. Involuecrés sessile... 2: Gis fe PS ABIStIeS MMOS ss... ee = 5 nce 2 hs on ee CeMEhroides: (Bristles Mot “MIUMIOSE (cP ca en, pe ee ec ene 4 4. Anther tips penicellate. Styles connate or * cohering for half their length. Lodicules 0... ... P. thunbergii. Anther tips naked. Styles almost free. Lodicules Eg GISHMCh sas" ho tite eee PEEP ee Cre RS OS, ey 5 43 5. Culms pubescent or hirsute below the panicle. Blades 6. very narrow. Panicle 2-4 in. long ... P. sphacelatum. Culms glabrous, smooth or scaberulous below the panicle. Blades 2-4 lin. broad. Panicle up to 1 ft. HOW Ac. 5 PALWekt, aueagii. otter ost Si sk wee 96 Panicles 34-6 lin. thick. Spikelets 2-2} ‘lin. long as P. macrourum, Panicles about 3 lin. thick. Spikelets 14-12 lin. long. P. natalense. PENTAMERIS. ds Valves and pales very broad. Lobes of former broad, short, dentate or abruptly subulate-acuminate ... P. thuarii. Valves and pales narrow. Lobes of former long, narrow, acute, adnate for re of their length to lateral restless: 27. e: PERS Peer Oe NA oat tee ete 3. Panicle very lax, more or less open ... P. longiglumis. Panicle narrow, contracted: .... ..... eae cee eat aatek AE 4. Spikelets 8-12 lin. long. Awn 9-11 lin. long. Lobes of valve 5 as long as pody .s2s:..... ... «. Ps speciosa. Spikelets 63-74 lin. long. Awns about 6 lin. long. Lobes of valve 4 as long as body... ... ... ... P. dregeana. PENTASCHISTIS. 1. Panicles eglandular. Spikelets more than 3 lin. long 2 Panicle or leaves or both gland-tubercled, or if eglandular then the spikelets less than’ 3 lin. long <..-... ... 18 2. Blades 3-14 in. long, more or less subulate ... ... 3 Blades 12 it. long, “fiform, convolute: :.. -..3° 2. 5) 3. Annual. Spikelets 7-8 lin. long. Blades soft. P. triseta. Perennial. Spikelets 3}-43 lin. long. Blades rigid... 4 4. Axils of panicle long bearded ... .:. ... .:. ... P: acimosa. Axais.of panicle slahrouys .... dn ..+...0) a0: 2c.) 2. Pe ielegans. 5. Basal sheaths at length breaking up into persistent fibres. Spikelets 3-43 lin. long . 6 Basal sheaths not breaking up into persistent fibres. i 6. Blades setaceous, subterete, glabrous. Awns scarcely exserted . ; P. tysoni. Blades up to 1 lin. broad when unfolded, pubescent above the ligule. Awns exserted from the glumes . P. fibrosa. Me SIKCleISs G22 LIM GONE. soa ecS i ess ccs, loco see sce ee scp vse™ 8 SHOMCEIC (SEA LI MAM sec tA caneehe aes enkincelees, od ced ees | i 10. i La 13. 14. 16. 17. 18. 19. 20. 44 . Panicle 6 in. by 6 in. effuse. Side bristles 2-23 lin. long. P. natalensis. Panicle 2-4 in. flaccid. Side bristles 5-63 lin. long .. P. capensis. . Panicle obovate when contracted. Basal sheaths silky tomentose ... ... nites) AO Panicle oblong to ovoid. Basal sheaths not silky tomen- tose . Beet OS ee acer Ae Spikelets 78 lin. ‘long . alee ita ep aristidoides. Spikelets 5-6 lin. long . . P. viscidula. Blades rather broad, flat, or loosely folded aan cre 12 Blades very narrow, filiform, convolute ... ... ... 13 . Spikelets brownish, straw coloured. Keel of elume smooth. Side bristles of valve stiff, 2-24 lin. long. P. pallescens. Spikelets silvery, Senne: Keel of glume ciliate. Side bristles slender, 4-5 lin. lone 9s. 282. P. argentea. Panicle spike-like ..)...00 52. 2.060... “aa. BS eurvitelia. Panicle not, Spise-like. 22e 4; eee eee ee Reece Panicle 2-3 in. be Lax, eee es Bl ades 4-1 ft. lorie y sac .<. SER Nada Sane eee ap ae P. colorata. Panicle 4-10 in. ‘long, usually dense. Blades 1-240, LOIS Besar. 5 Baan nt eee er eee oe . Sheaths broad. eee rome ued 46 Sheaths narrow. Blades channelled. _ Ligular fringe straight .. eee a, aie 8) Spikelets os 6 ia tone. poiumes suhag Ban Pp. nutans. Spikelets 44-43 iin. long. Glumes scaberulous on_ the kee] . bee aie piace . P. tortuosa. Sheaths densely oni or yalleas in ane upper part, lower often sub-flabeilate ... ..... . P. eriostoma. Sheaths adpressedly hairy between the nerves, at length glabrous, not flabellate ... ... ... ... ... P. juncifolia. Panicle very slender, acute, about 5 ins. lone ... P. lima. Panicle obtuse in the contracted state, or if acute then much less than 5 in. long ... ... epee TaN eee a 1, Culms erect, rather stout. Panels 3.6 in. chee Blades rigid often flat . poe.) Culms ascending (or if erect then annual ¢ or panicle 3-3 in. long or: blades not flat and broad)... <5. .c 12. snearce Panicle contracted, rather dense, ene unequal. “P. zeyheri. Panicle open, lax, all divisions except the ultimate 45 Axis and branches of panicle scabrid, without tubercular glands. Glumes smooth ... ... . P. hirsuta. Axis and branches of panicle with tubercular glands. Keels of glumes scaberulous ... ... ... ... P. rupestris. Annual . ; ; A are 23 Perennial Vette 25 . Spikelets 14-13 lin. long. “Anthers ‘at lin. long . P. airoides. Spikelets 2-24 lin. long. Anthers 1 lin. long ... ... 24 24. Panicle lax, divaricate. Blades filiform or involute .. P. patula. Panicle more or less contracted. Blades flat. P. euadenia. 25. Spikelets 3-4 lin. long . UPC mesa ee denise wine OU Spikelets scarcely 24 lin. ‘Jone . ac cue eo 26. Blades closely and prominently ‘striate, curling at length. ei. Margins fringed with numerous tubercles. P. aspera. Blades slightly striate not curling. Margins not or scantily tubercled . : : eT Culms densely and distichously le aly at the base. ‘Ligular fringe inconspicuous. Sheaths coer bearded or Wear dleSsyees..a) sis: . P. subuliiolia. Lower leaves fewer or more distant. Ligular fringe conspicuous. Sheaths bearded ... ... P. leucopogon. . Spikelets 21-4 lin. long. Blades cas filiform or EPIC C OS it ass rosea ates ta i et Sods Saal poe ASE tate ows Sle Spikelets 1-23 lin. long. Blades soft or “flaccid Or iif somewhat rigid, then very fine or very short ... 33 . Side bristles 3-4 on each side of the valve ... P. heptamera. Side bristles 1 on each side of the valve” Saath nota emmeses ) . Spikelets 33-4 lin. long. Blades setaceous, glabrous 1-4 in. lone) Br Aad ahah Aen aiaues: er DUT CRELIN. Spikelets 21-3 lin. long . ; dies BAAR oe . Lower valve with 3 bristles. Upper “with | a long kneed awd amd 2 bristles)... <.. ihieecer toa P. heterochaeta. ot valves-alike <...... .- top eee . Blades very hairy 1-44 in. ~ lone. ~ Glumes “pubescent. P. tomentella. Blades glabrous or scantily hairy. 2-8 ins. long. Glumes elabrous 2.2... : P. angustifolia. : Panicle very lax, open. ‘iat least temporarily) es 34 Panicle contracted, usually dense ee open in P. thunbergii) . ee co . Valves with the lobes gradually ‘passing ‘into bristles. Blades small, hairy .. . P. jugorum. Valves with the lobes distinct ‘fr om the bristles Sains 35 36. 46 5. Culms 3-4 ins. or rarely longer. Blades flat, 3-1 in. long. P. densifolia. Culms 9-18 in. long. Blades 2-6 in. long, finely filiform OL SCLUECOUS © 002) Blotae eee aceeaaey eee Pr ea we ter a 36 Both valves awned; lobes feaeieme ss tets 2. Diormis: Lower valve awnless (usually); lobes acute ... P. imperfecta. 7. Glabrous. Lobes are into bristles. Awn short and PIMC ges coco Eee . P. brachyathera. Valves usually hairy. Pine actinic aa the bristles. Awn kneedandexserted™ 7.4 22e. ee eee OO Panicle 4-3)in. long. | Pedicels short”. 2... Pp. thunbergii. Panicle 5in. long. Pedicels long and fine ... P. longipes. PHALARIS. Annual. Keels of glume conspicuously winged . P. minor. Perennial. Keels of glume not or obscurely winged. P. arundinacea. POA. ile A. Or Annual or sub-perennial. Anthers less than $ lin. long. P. annua. Perennial, Anthers-t or moresine |OMGs- 49...) ee . Bulbous at the base. Leaves of barren shoots often filiform ae ae ee, P. bulbosa. eee fee 9 Not bulbous. ae Aat finely filiform Sc Bor ae ee . Valves glabrous or almost so, not connected by wool. Basal sheaths breaking up into fibres ... P. binata. Valves connected by long copious wool 4 Spikelets elegantly variegated. Branches of panicle 2 nate. Pantele lax vis 1 oo es ado. athierstonei: Spikelets not or scarcely variegated. Branches of panicle 3-6 Mate i. 2. Sis Madi ye WAR Ini SOON tae SI hepato ote 5 Culms compressed. Valves minutely 2 footed | Ee bidentata. Culms térete or sub-compressed below. Valve entire. P. trivialis. POLLINIA. Perennial. Culms erect. Veld plant ... ... ... P. villosa. Annual. Culms delicate, decumbent, rooting. Bush plant. P. nuda. POLYPOGON. Aw ot-elumes: 2-3 ling long... ... ... P. monspeliensis. Awn of glumes up to 1 in. long. Side nerves of valve excurreniminto Dristlés Ax .2: c.. ..4 2... P. tenuis: PRIONANTHIUM. Lateral nerves of the glumes close to the keels. Mem- branous margins very broad... ... ... ... P. rigidum. Lateral nerves of the glumes more equally distributed. NA OTIS MALTOW tack Sco 0te cee ce see. ec< doe. ewok CCKIONI. SCHISMUS. 1. Aw : of valve 2-3 times the length of the lobes. Anthers | lin. long . . S. aristulatus. V ae without o or b with: a mucro, not ¢ or r slightly exceeding the lobés, Anthers 7-7 lin long .:. ... : 2 2. Spikelets narrow. Glumes thin, acute, or “acuminate. S. fasciculatus. Spikelets slightly turgid. Glumes somewhat firm, sub- GUUS Cavey seat ae tees Se eae, ced eae oe econ nes es, KOPLEDIOIGES. SETARIA. 1. Blades broad and plicately folded when young. Panicle open or almost spike-like ... ... .. Bon tee, Blades not plicately folded. Panicle spike- ‘like Ree, Oe 3 . Culms 5-12 ft. long. Blades 1-3} inches broad . S. sulcata. Culms 2-3 ft. long. Blades less than 4 in. broad ... S. lindenbergiana. aublades deeply sagiltaté. 1. .6.... st. 22. Se ie a leaati (w) Blades not sagittate .. ; 4 4, Annual. Panicle cy lindric often. lobed, ‘dense. or “Tax 9) Perennial. Panicle cylindric always dense ... ... ... 6 5. Bristles of panicle with barbs reversed ... S. verticillata. Bristles of panicle with barbs pointing upwards ... 6 6. Culms slender weak. Blades 2-6 in. by 1-3 lin. Panicle Fone Dyed y— 2 Wie. .S. imberbis. Culms often stout. Blades 6- 18 in. . by 3- 10 lin. Panicle Ail Ve 4d SeNI 5s eey cocks way co isnt Oe OD SMALE: 7. Lower glume 5, upper 7 nerved . cts ered een 2 Lower elauie 1-3, upper 5 nerved . 9 8. Blades 3-4 lin. broad. Tips of bristles thick and blackish. . S. nigrirostis. Blades 41-2 lin. broad. Tips of bristles not thickish. S. gerrardi. 10. 48 . Culms 2-3 noded #-2 ft. long. Panicle 3-2 in. long ... 10 Culms 3-7 noded 2-6 ft. long. Panicle 2-42 in. long... 44 Blades setaceously convolute 3-2 lin. broad ... S. perennis. Blades folded or flat 1-2 lin. broad (unfolded) ... ... S. flabellata. 11. Culms very rough for a long distance. Bristles coarse. S. rigida. Culms scabrid close to panicle only. Bristles slender. S. aurea. SPOROBOLUS. 1. Rachilla produced into a short bristle subtending the floret . ea dae! kopadis, she eee | pe SUE ULLESS Rachilla long, not produced . a ees 2. Culms very many noded. Leaves often apparently oppo- Site pions CUM ses cess eee te, we reomaee . S. pungens. Culms: 4 moded: Or Wess” sets.) 5° she sctedon PSone eee ee 3. Spikelets 13-2} lin. Be Panicle ovate or spike-like, GS IULOKEIE COlSIMSery Gone out ss aus aoe Ds CCMIEMUGUS: Spikelets 3-44 lin. long. Panicle lax, or if dense then long and narrow ...... . Late a oh Seed Bea ara 4. Culms from a few inches aol fl. tone, Beene few money, raseu eee eet 5, Culms 2-4 ft. long, rather robust, 2. 4 noded . Sic Baie aes Dt 5. Culms with a dense tussock of fibres at base ... S. festivus var. stuppeus. Culms not with a dense tussock of fibres at the base 6 6. Valves 3-nerved, exceeding the glumes ...... ... . x Valves 1-nerved, about as long as upper glume Aen es) 7. Panicle contracted, somewhat spikelike. Spikelets pallid. 1 lin. long .. hin! inl idle: Ile tthan aa Goa Sekt Se OATES 6 Panicle effuse or ‘lax. “Spikeiets purplish, 54 lin.long 8 8. Culms 2-6 in. long, 1 noded. Testa mucilaginous .. S. tenellus. Culms 9-12 in. long, 2-3 noded. Testa not mucilaginous. S. acinifolius. 9. Blades denticulate, fimbriate ... ... ... ... S. disecosporus. Blade margins smooth . Patty To Eamets Ba sate |) 10. Rhizome creeping. Bareen shoots very - short, cylindric, CUStITCl ine. ee Saas S. ludwigii. Rhizome oblique. Barren shoots “much longer, in com- Pact wuitSs ce. v2. wees fn eae dae: Se OCIAG@OS: 11. Upper glume slightly exceeding 4 Secale ce ee S. indicus. Upper glume equalling or slightly exceeding the valve 12 49 12. Panicle at oon rather lax. Blades mostly flat, 3-4 lin. broad . S. rehmanni. Spikelets crow vded on the branchlets, ‘often secund. Blades MALLOWEL, COMVOIULE 2. se. cnn kee . S. fimbriatus. STIPA. Annual. Blades fine. Panicle spike-like. Awns long, intertwisted . ; Speer anita see ec COLES Perennial. Blades flat. "Panicle large. Awns short, twisted at base only. 7.) 20.0... ..c5 03s. Se. regeana. TRAGUS. Uppermost internode long exserted. Anthers 1 lin. long. T. koelerioides. Uppermost internodes enclosed. Anthers 3-} lin. long. T. racemosus. TRICHOLAENA. 14. Spikelets glabrous ... ... Scere arene cued lag iE Tite P Spikelets pubescent or villous Sa pi ake ogee ae Ee 2. Upper glume and lower valve 2-3 lin. long gibbous at or below the middle SSF us 3 Upper glume and lower valve it lin. ‘long or rather longer, HHO tre SMG OUS 50 aes lycine woe weet ook cose lage 's eae 5 sblades setaceous. ... ... TE oer Re T. setifolia. Blades flat, rarely convolute WR Pe Pea aya te spikelets silky, villous: ..< ....: sultces seeets eb on POSER. Spikelets adpressedly or scantily hairy - ee? T. brevipila. 5. Spikelets loosely villous. Lower glume about $ as long as spikeletic.. >... srs a is capensis. Spikelets pubescent. Lower glume minute . . T. arenaria. TRICHOPTERYX. 1. Spikelets 2-3 lin. long. Valve of male floret long bearded below. the middle: s2r..c a. eye. T. dregeana. Spikelets 3-7 lin. long. Valve ‘of male ‘floret pubescent, not bearded except at the callus . Stl tgee sre 2. Suffrutescent. Valve of male floret sub 7 nerved ... T. ramosa. Not suffrutescent. Valve of male floret 3 nerved ... 3 3. Valve of hermaphrodite floret 7-5 nerved. Callus 2-toothed at the base ... ... . .. T. simplex. Valve of apeneenes floret distinctly 9 9 nerved. Callus MEDVE GCULG: 42 fa. 5-5 ces ce stwka ee (eee. oe . T. flavida. TRIRAPHIS. AP EHEINTMAlae ate) setae tae OE ee ea Aa SAD. ot Ne Pa wig ATAU ai bess Gace. Ui hy Sete ece tone) ee oe eee aee a8 vag. ahaa ney 2. Culms many noded, profusely branched. T. ramosissima. Culms about 3 noded simple ... ... ... ... ... T. rehmanni. 3. Valves 2 lin. long. A dwarf grass ... ... ... ... T. nana. Valves about 15 tin. lone 2.2... : 4 4. Culms 5-7 noded. Middle awn about ‘twice length of the Wallet teccns gees: . T. elliotii. Culms 41-2 noded. "Middle ¢ awn 1 about as ‘long. as valve 5 5. Culms with scattered, long, Ue hairs Glumes SUMO. Oa ees eee eee os ss ee ehs T. fleckii. Culms glabrous, eeahernlone or - sometimes scantily hairy. Giuimiesm Scale rulous 7.0 aes meee teeters . purpurea. TRISTACHYA., AG UIMes) Slab OWS) jc) secre sees T. rehmanni. Glumes hairy with pristle- bearing glands ee 3 Anes A eee pales Vequal 40" lin: VWOne sack cucr see eee DISeriaba Glumes unequal, lower 9-12, upper 14-18 lin. long ... ; T. leucothrix. UROCHLAENA. Culms 3-4 in. long, 3 noded . ater ... U. pusilla. Culms 4-6 in. long, 4 noded (perhaps “only a robust variety of U. pusilla) ... ... Sls ieee talk ... U. major. VULPIA. Uppermost internode enclosed. Upper glume 1 nerved. V. myurus. Uppermost internode long, exserted. Upper glume 3 MOLVEC calli cdt lke ean cose tens aauieeee. vedohes eV ee LOMMOILeSe III.—Ecological Notes on the Principal Species in each Genus. — In this section it is my purpose to set forth the principal facts that have been ascertained, regarding the part played by all the more important species in the grassland plant suc- cession, and also by means of selected examples, to illustrate the general differences, which are shown in morphological characters, and particularly in leaf anatomy. Much may be learned by studying simple transverse sections of the leaves of grasses. It is much less laborious, and probably even more useful on the whole than elaborate chemical analyses of the herbage, for these without doubt vary greatly according to the time of the year, and even according to the state of the weather. Leaves which after a spell of dry sunny weather may be found full of storage food, may, after a few weeks of rainy, cloudy weather, contain relatively little starch. Farmers have repeatedly expressed the opinion to me that during the past season of exceptional rains, and cloudiness with low tem- peratures, the veld grasses, though they grew well, especially in the drier low veld, were less nutritious than usual. ‘Chemical analyses therefore to be of value should be repeated at intervals throughout the season, and this, so far as I am c-aware, has seldom been done. In attempting to gauge the feeding value of a grass from its ecological behaviour and its morphological appearance, it should be remembered that there is a very close connection between the two processes of transpiration (or loss of water) and carbon assimilation, since the stomata are involved in both processes. Water is lost through the stomata and carbon ‘dioxide is taken in through the stomata. Now a grass which is forced to protect itself against excessive transpiration (7.e., a xerophytic grass) must at the same time be hampered in its carbon assimilation. Xerophytic grasses therefore cannot grow so quickly, and are not so valuable for pasturage as the more mesophytic types. There are few general rules of this kind which do not admit of exceptions, however, and some xero- phytic grasses, e.g., Danthonia purpurea (see Fig. 9), though their leaf surfaces are greatly reduced, tend to become some- 52 what succulent, and though slow-growing this species of Danthonia is a very matneieee orass. The same apples to other Western and xerophytic species. Another feature of xerophytes is a tendency towards increased lignification. The leaves become very hard, having developed a large amount of fibre or sclerenchyma. Even though they sometimes contain a fairly high percentage of starch and proteids, etc., cattle dislike them, and refuse to eat them, if they can get any other kinds. It is very notice- able how they eat out the more mesophytic species first, from mixed Veld. In the various figures of leaf sections here reproduced the sclerenchyma is shown by cross hatching. A glance is sufficient to show whether each grass represented is likely to prove palatable to stock. The less cross-hatching shown, the more useful the grass from this standpoint. All the ordinary grasses have their veins or vascular water-conducting strands parallel. These may be seen by holding the leaf up to the light. The principal veins lie ‘underneath more or less prominent ridges which have furrows between them. Some leaves have a midrib which is larger than the other veins, others do not. A comparison of the figures will show that the ridges are very prominent in the more xerophytic grasses like Arzstida, and in all the temperate types like Achneria, Lastochloa, Pentaschistis, Ehrharta, Dan- thonia, Brizopyrum, while they are much less prominent or almost obsolete in the sub-tropical tribes of the Andropogoneae, Paniceae, etc. (Andropogon, Anthistiria, Urelytrum, Setaria, Tricholaena, Panicum, Digitaria, Sporobolus, Harpechloa, Chloris). The sections also show that there are often one or two smaller vascular strands in the hollows between the larger ones. ‘I'he arrangement of the sclerenchyma is also interesting. It usually hee above and below the main veins, 1.€.,801 the ridges and opposite to them on the lower side. In the mesophytic types it does not join up to the vascular bundles, but in less mesophytic types it forms a girder, which crosses the leaf, the vascular strand lying in the middle of the girder. In still more xerophytic species (e.g., Aristida bipartita, Danthonia disticha) it forms a continuous band along the lower surface. Attention should also be directed to the presence or absence of hairs on one or both surfaces of the leaf, to the relative thickness or thinness of the cuticle, to the nature and size of the epidermal cells where these are shown, to the arrangement of the green chlorophyll tissue, and to the general outline of the section. 53 e Particular attention should be directed to the way in which the leaf is folded. Some of the xerophytic forms are permanently folded, e.g., Danthonia, some of the more meso- phytic ones are permanently flat, e.g., Anthistiria, Digitaria, etc., but intermediate between those are a large number which have their leaves flat and unfolded under moist conditions, and folded on the midrib (conduplicate), or rolled in from the margins (convolute), in dry weather. In such leaves some of the cells of the upper epidermis (either those above the mid- rib, or those in each of the hollows between the ridges) are- larger and thinner walled. When they are full of water and turgid, as is the case when their water supply is not restricted, they keep the leaf unfolded or the ridges apart. In dry weather, however, they lose water and more or less collapse, which has the effect of drawing the two halves of the leaf blade together or causing it to roll inwards from the margin. The experiment may be tried with ELragrostis curvula, which is so common along the roadsides in Spring. Pick a few leaves of it when they are flat and expanded and allow them to lie for a few minutes in the sun. They very soon roll up from the margins. In such grasses the thin-walled cells. referred to are known as ‘‘motor cells.’? Similar thin-walled cells occur on the leaves of Andropogon, Digitaria, Setaria, which do not, at any rate readily, fold or roll up. In this case they do not function so much as motor cells, but rather as water storage cells. An examination of the figures will show that in such cases the water storage cells are more numerous, covering in some cases most of the upper surface, and there are no prominent ridges. There are other more minute points of structure in grass leaves which are fairly constant, and are useful for the purpose of distinguishing species by their leaves, but it is not my purpose to discuss these at the present time. The chief species will now be dealt with individually, the genera again for the sake of convenience of reference being arranged alphabetically. Achneria- (See Fig. 1.D.) A temperate genus found chiefly in the South Western region. It differs from Penta-- schistis in being awnless. A. capensis is an important species in the early stages of the xerosere. It invades moss carpets on bare sandstone or granite rocks, and remains for a short time dominant. A. ecklonw and A. ampla favour marshy or wet sandy soils, and belong rather to the hydrosere. The others occur sparsely scattered among the Macchia shrubs of the- S. West, and are of little importance in the plant succession. 54 Three species, viz., A. microphylla, A. hirsuta, and A. setifolia have a more eastern distribution, being characteristic of the Karroo mountains, and the Stormberg and Drakens- berg. A setifolia sometimes forms small societies on the flat dry plains of the Eastern Karroo, and transitional belt between that and Eastern Grassveld, and is a good grazing grass. All the species of Achneria are very xerophytic with narrow, short, folded, or setaceous leaves, and deep roots. The spikelets are more or less shining or glistening. The cross section of a leaf of A. capensis is shown in Fig. 3. Note the abundant sclerenchyma, which forms large girders, the pro- Fig. 3—Transverse Section of a leaf of Achneria capensis (x about 120). “minent ridges and motor cells, the thick cuticle and the large lower epidermal cells. There is no definite midrib. The unshaded portions between the girders is all green chlorophyll tissue, usually found packed full of food. There are no -smaller vascular strands between the main ridges. Agropyrum distichum. s / L With the exception of the tufted caespitose forms like P. natalense the majority of the species of Panicum are meso- phytic or hygrophilous, and are tropical in their affinities, in fact the majority of them are confined to the frost free locali- ties in South Africa. Their leaves are flaccid and often deli- cate without much sclerenchyma, and without pronounced ridges, resembling those of Setaria, Digitaria, Tricholaena, or Tristachya. The chlorophyll tissue sometimes surrounds the bundles, in other cases it is distributed evenly along the central line, and has water storage tissue above and below. fo) There are often fairly large intercellular spaces. Paspalum. P. scrobiculatum (isAmuyisane) is common as a weed in cultivated land, and also in Vleis in Eastern Cape Colony and Natal. It is eaten by stock, when it is young, but as the seeds begin to mature it becomes poisonous. P. distichum is fairly common in the coast Vleis of Natal. Several other species have been introduced, e.g., P. digitaria (at the Cape), P. virgatum, and most important of all P. dilatatum, which has been found to be a valuable grazing and fodder grass. It is widely grown and is capable of holding its own against the indigenous grasses. The Paspalums resemble closely the Panicums of the section Brachiaria with secund false spikes. Pennisetum. This is typically a Vlei genus, but P. typhoideum is cultivated by the natives sometimes and occurs in moist waste land. P. cenchroides is also often ruderal, but sometimes occurs on stony hillsides as well as along streams. P. macrourum is chiefly South Western and Central, ie natalense, P. sphacelatum, P. wnisetum are Eastern, and P. SU thunbergii occurs ali over South Africa. They are all Vlei and stream-bank species, but they rarely assume dominance. They are very like the Setarias, but are easily distinguished by the fact that the bristles fall off with the spikelets. Penna- setum longistylum (the Kikuyu grass), a native of East Africa, has recently been introduced into cultivation in South Africa. Pentameris (Temperate). A distinctive endemic genus nearly allied to Pentaschistis, from which it differs only in the characters of the ovary and fruit (see key). It consists of five species which are confined to the Macchia region of the Cape. P. thuarit and P. speciosa are the commonest. All the species are extremely xerophytic with woody or suffrutescent bases, deep roots, and rigid wiry leaves. They grow in isolated tufts among the shrubs of the Macchia. Pentaschistis (Temperate). A large endemic African eenus of over forty species, separated by Stapf from Danthonia by its endemic distribution, habit, and reduction of the florets to 2. Only a few species occur outside South Africa in the tropical parts of the same continent, and in South Africa the majority of the species are confined to the South Western region. Some of the species belong to the early stages of the xerarch succession to Macchia, e.g., P. tortuosa, P. pallescens, P. thunbergii, and P. angustifolia. Most of the species, how- ever, occur among the Macchia shrubs at the climax stage as isolated individuals or as small clans or societies, the com- monest being P. curvifolia, P. arvistidoides, P. pallescens, P. colorata, P. argentea, P. capensis, P. acinosa, P. aspera, P. angustifolia, P. thunbergii, and P. aeroides. In Pentaschistis, as in other characteristic Cape genera, there are a few species which have a more Eastern distribution. Around Grahamstown there are P. curvifolia, P. fibrosa, and P. longipes; on the mountains of the Karroo near Graaff- Reinet P. angustifolia and in Calvinia P. heterochaeta; still further east on the Witteberg at altitudes of 7-8,000 feet P. jugorum, on the Drakensherg and Stormberg P. aeroides, on Mount Currie near the Natal border P. tysonz, and in the mountain regions of Natal itself P. natalensis. Some of the species are confined to that northern outher of the South Western Flora in the mountains of Namaqualand, e.g., P. tomentella, P. filiformis, P. brachyathera, P. euadenia. Si Pentaschistis like all the other Cape genera (Achneria, Danthonia, Pentameris, Avenastrum, Ehrharta, Lasiochloa, Brizoyyrum) shows extreme xerophytism in all its features almost without exception. There are deep roots and filiform or setaceous (sometimes flat) leaves. In a large section (see key) the leaves are gland tubercled. The spikelets are more or less glistening. Fig. 17 shows a cross section of part of a leaf of P. curvifolia. The margins are slightly thickened, and there are prominent ridges. The main bundles are very strongly gir- dered and the sclerenchyma forms a continuous lesa along the lower surface. There are smaller bundles which are na girdered. ‘There are motor cells in the grooves, and the cuticle is thick. There is no distinct midrib. Fic. 17.—Transverse Section of a portion of a leaf of Pentaschistis curvifolia (x about 70). Perotis latifolia, a tropical species found only in S. Africa on the coast belt of Natal, and the northern Transvaal and Amboland, though it extends through the tropics of Africa and Asia. Phalaris. Ph. arwndinacea is common in vleis, ditches, and around the margins of Bush. It is widely distributed. Ph. minor is an introduced weed, and Ph. coerulescens (= Ph. bulbosa) is cultivated for grazing—a valuable grass. Phragmites communis, the cosmopolitan Reed grass which occurs all over South Africa, and is the most important grass in the hydrosere, often lining the rivers for miles and occurring abundantly in Vleis. Poa (Temperate). Poa bulbosa is only recorded for the West. Poa atherstonei is a very rare species from the Com- pass Berg. Poa annua, Poa trivialis, and Pot pratensis are all introduced species. The only important South African species 82 is Poa binata, which is common in Mountain Veld. It grows usually sparsely scattered, and it prefers moist spots. It is a very good grazing grass. Poagrostis pusilla is found in shady, moist places on Table Mountain, Capetown, not elsewhere. Pogonarthria falcata is associated with Lragrostis guin- miflua as one of the dominant grasses on the dolomite soils of the Transvaal, and it extends northwards to the Zambesi. It occurs also on the coast belt of Natal. It resembles specces of Hragrostis, its leaves folding up convolute. They are often rigid. Pollinia. The two species of this genus are very distinct. P. villosa is rather common in the coast Veld of Natal, and occurs also in the Transvaal and the South West. LP. nuda is a shade-loving slender, rambling Forest grass, also found in India. It never occurs in the Veld. Polypogon. P., tenuis is South Western extending east- ward to the Witteberg. P. monspeliensis (Beard grass) is very widely distributed over the whole of South Africa. Both are Vlei or stream bank or moist sand dune species. Potamophila prehensilis. A shade loving Forest species confined to the coast of Natal. There are only three species in the genus, one in Natal, one in Madagascar, and one in New South Wales. Prionanthemum. Al] the species are rare and South Western. : Pseudobromus africanus. Only recorded from the Trans- vaal Houtbosch. Rottboellia compressa var. fasciculata. A Vlei or stream bank species extending from the Cape to Natal. Not common. Saccharum munroanum is another Vlei and stream bank species rather rare in Natal and the Transvaal. Schismus. S. fasciculatus is the only common species, and of it there are several varieties. It occurs at the Cape, but it is chiefly characteristic of the drier regions of the West and the Karroo. It is a small tufted annual. Schmidtia bulbosa (Zand Kweek gras). One of the most important species in the Sand Veld of Griqualand West and 83 Bechuanaland, also in the Free State and Transvaal. It is xerophytic, nail convolute leaves, and numerous villous, conical, innovation buds at the base. Hence it is more or less bulbous. Hackel distinguishes other species, viz., S. quinque- seta and S. pappophoroides, from various places in the Kala- hari, Namaqualand, Hereroland and Amboland. Scleropoa rigida (= Poa rigida L.), an annual ruderal species introduced at the Cape. Secale africanum. Collected by Thunberg on the Rogge- veld, which, he says, were named after this rye grass. Setaria. (See Fig. 2D.) The two species S. sulcata and S. lindenbergiana of the section Ptychophyllum are very distinct from the others. They have broad leaves which are plicately folded when young. The former is the more abun- Fig. 18.—Transverse Section of a portion of a leaf of Setaria nigrirostis (x about 70). dant, being usually found round the margins of Forest. S. perennis is a Veld species, S. verticillata a widely distri- buted weed, and the rest are Vlei species. S. aurea often forms definite consocies in the hydrosere. With the exception of S. appendiculata, which is Western only, the Setarias are Eastern in their distribution, being closely allied to the Panicums. Fig. 18 shows the appearance of a leaf of SN. nigrirostis in cross section. The ridges are not pronounced, and the bundles are not girdered, there being only small patches of sclerenchyma above and below the main ones. There were usually three smaller bundles between the larger. The midrib is distinct, but the large cells in the shallow grooves function as water storage cells and not as motor cells. The leaf remains flat. Spartina stricta. A European strand and salt marsh plant, only found in South Africa along the seashore at Port Elizabeth. 84 Sporobolus. (See Fig. 2 I.) This is another important genus of pioneer species like Arzstida and Eragrostis. There is one group of smal] xerophytic forms, which are particularly characteristic of stony plains and hillsides in the drier regions. Sporobolus densissimus, S. panicoides, S. nebulosus, S. rangei, S. robustus, S. virginicus occur in the Western region. In the Sand Veld region there are S. tenellus and S. acinifolius. In the Karroo and the trausitional belt to grassland S. toclados, S. ludwigu, S. albicans, S. discosporus are the distinctive species. S. festivus var. stuppeus is a tussock forming species in open or mountain Veld of Natal and the Transvaal. It forms a dense and characteristic stool of old leaf bases which break up into fibres. S. centrifugus is a mountain Tussock Veld species, though it is recorded also for the coast belt of Natal. S. fimbriatus is impertant in open transitional Veld chiefly, but it occurs in the Veld of Natal and the Transvaal. S. rehmannt is a tropical species of the Transvaal and Natal coast belt, while S. subtilis occurs in the latter habitat and also in Madagascar. Fig. 19.—Transverse Section of a portion of a leaf of Sporobolus indicus (x about 60). The most widely distributed, and also the most important ecologically, is S. indicus (umSingizan). It is fairly common among the Macchia of the South West, and is very common as a ploneer species in eastern Grassveld. In Natal the more robust variety lavus covers wide areas of primitive Veld, often associated with Hragrostis plana (umTshiki). This Sporobolus- Eragrostis associes becomes semi-stable often as the result of continuous grass burning. umSingizan is also common along roadsides and railways. Its leaf is shown in transverse section in Fig. 19. The ridges are not prominent, but there is a distinct midrib. The sclerenchyma is not excessive, and the bundles are not girdered. The motcr cells are functional, and the leaf rolls up in dry weather. Sporobolus indicus is eaten 85 by stock especially in Spring, aud is cut for hay, but it is not considered a very good grass. The Mountain Veld species, S. centrifugus, is better in this respect, but none of the species. are of much value. The species Sporobolus pungens is in a class by itself,. being the most widely distributed strand plant in South Africa. It extends right round the coast from West to East, and often forms very definite consocies within reach of the salt water. It also occurs in salt Vleis near the coast. It varies a good deal in form, but it may be easily recognized, even when not flow ering, by the peculiar many noded culms, which are sheathed all along and have the alternate internodes very short so that the subulate-involute pungent leaves appear sub-opposite. It has a creeping rhizome and is stoloniferous. It is a common litoral species in most warm countries. which roots at the nodes, and prefers a sandy soil. Tt is dominant in the hillside flushes very often in the Cape region, and it also forms very definite consocies on moist sandy flats along the coast of Natal. It is used as a lawn grass (c.f. Dactyloctenium aegyptiacum), The leaves in cross section show the chlorophyll more or less surrounding the very numerous small bundles, and a large amount of nce storage tissue both above and below, which is unusual. There is very little sclerenchyma. Stenotaphrum glabrum is a prostrate creeping grass, Stiburus alopecuroides is found in moist places or forms consoczes in the hydrosere of Eastern Mountain Veld. Stipa. S. tortilis is an annual common in the South Western region and Namaqualand, and S. dregeana is a shade loving Bush grass, widely distributed not only in the Eastern 1 aheeteA but also in the stream bank Bush of the Karroo and drier regions. . Tetrachne dregei. A Mountain Veld species of the Storm- berg. It is sub-dominant in places or forms societies in the Haas eras Veld of the Molteno district. (See under Danthonia.) It is a xerophytic form with rigid convolute leaves and low tufted habit. Trachypogon polymorphus var. capensis is common in climax Eastern Grassveld, where it forms autumnal aspect societies. It resembles the Andropogon species with which it mixes. Its Jeaves are Jong, narrow, and more or less rigid. The type is found in Tropical and Sub-Tropical America. 86 Tragus. Both species (7. koelerioides and T. racemosus are most characteristic of the open Veld of stony hillsides in the region bordering the Karroo, and also of the Sand Veld region of Griqualand West and Bechuanaland, but 7. race- mosus occurs in similar situations in Natal and the Transvaal. They are smal]l xerophytes, with rather rigid leaves, which have spinulously ciliate margins. The olumes also have spiny hooks. They are reckoned fairly g good grazing grasses in spite of their xerophytic character. Tricholaena. 7. arenaria is important in the sandy plains of the West, 7. capensis is from the Central Cape and the Free State, fi brevipila from Namaqualand, all being xero- phytic species. 7. glabra is a rare Natal species. 1. setifolia is an important pioneer in the early stages of grassland over the Eastern side. It grows in compact tufts and has filiform, setaceously convolute leaves. 7. rosea in its perennial forms colonizes stony hillsides, and is widely distributed over the Fig. 20.—Transverse Section of a portion of a leaf of Tricholaena rosea (x about 60). drier regions from West to East, but the semi-annual forms are peculiarly characteristic of cultivated mealie fields, and waste land generally. It becomes completely dominant and forms a short-lived erass stage in the Sub-sere. Its native name is umKuana. Its seeds have been exported, and it has been grown in India and elsewhere under the name of ‘‘Natal Red Top grass,’’ but in South Africa it is not considered to be of much agricultural value.