for a part of the year, subsist and fatten the immense herds of buffalo, and the cattle of the hunter and emigrant. The buffalo grass grows in immense tufts, sending out stolons. These, in most herbar ium specimens, are only a few inches long, with internodes of onehalf to two inches in length; Lindheimer, however, sends specimens from New Braunfels, Texas, with stolons one to two feet long, the internodes often measuring over three, and even as much as five inches. The male plant seems to throw out more numerous runners than the female, and may often overspread, and kill it out, which would account for the much greater scarcity of the latter. Leaves two to four inches long, one-half to one and a half lines wide, sparsely hairy, or ciliate, or glabrous; sheaths striate, glabrous, strongly bearded at the throat.

The flowering stems of the male plant are four to six, or rarely eight inches high, mostly glabrous or very sparsely hairy, generally longer than the leaves, and bear two or three alternate oblique onesided spikes. These spikes are three to six lines long, and bear on the lower, outer side of the flattened, dentate, pubescent rachis six to fifteen minutely pulverulent spikelets, alternate in two rows; the uppermost spikelet is usually abortive, and is represented by a bristle. The spikelets are two or rarely three lines long, with two, or sometimes three sub-terete flowers; they are, as usual, among chlorideous grasses, somewhat obliquely distorted; the glumes are broader on their lower side, but turning upward, toward the upper end of the spike, they cover the upper edge of the flowers, leaving the lower edge free. The smaller lower glume is, as in this whole tribe of grasses, inside of the spike, and the larger upper one outside, and much more conspicuous.

Lower glume ovate-lanceolate, with a scarious margin, convex, scarcely carinate, one-nerved, obtuse or acutish, or mucronate, onefourth the length of the flower; on the uppermost spikelet of each spike, it is much larger, and almost equal to the upper glume.

Upper glume twice as long as the lower one, much wider, ovate, obtuseish, with a strong middle nerve, which sometimes runs out into a point or a short awn between two membranaceous teeth; in a specimen from Fort Kearney, I find on the lower side, a second nerve running out into a lateral tooth; a third nerve on the upper side is very indistinct; other spikelets of the same specimen show the ordinary structure.

Lower palea convex, obtuseish, three-nerved, middle nerve in the lower flower running out into a mucro; in the upper one mostly even with the membranaceous margin.

Upper palea as long as, or a little exceeding the lower one, which partly envelops it, two-nerved, two carinate, obtuse and scarious at tip. Scales, lodiculæ, two at the margin and inside of the lower palea minute, triangular-truncate, undulate or emarginate.

Stamens three, scarcely exceeding the paleæ; anthers linear, bifid at both ends, one line long; filaments much shorter. Pollen grains of the dry anther, immersed in water, globular, smoothish, .017 line in diameter.

The stalk of the female plant is much shorter than the leaves, nsually one and a half to two and very rarely three to four inches high; it is leafy to the top, the broad ventricose, many-nerved sheaths of the two to three uppermost leaves serving as involucres for the flower heads. These heads, three to three and a half lines long, are usually two in number, one almost sessile between both top leaves and on the side of the lower ones, the other on a flattened pedicel on the side of the upper leaf, sometimes a third head is noticed still higher, and on the side of the lowest one. The pedicels of these heads are nothing but the common peduncle or rachis terminating the stem, and the heads themselves correspond to as many lateral spikes of the male plant, in position as well as in structure; they are only more contracted, consist of fewer one flowered spikelets and turn obliquely upward, while the male spikes turn obliquely downward; where the number of spikelets does not exceed three, the head is ventricose-cylindric, or in fruit, subglobose; but when the number is larger, it is compressed and laterally elongated, showing distinctly enough the bi-serial arrangement. The pistillate spikelets are like the staminate ones, arranged so that the lower glume is inside and the upper one outside in the head.

The thick rachis of these heads is firmly united with the upper glumes, which in fruit become ligneous; they have a pale whitish or straw color, and smooth and shining surface, with a few scattered hairs; at maturity they separate entire from the common peduncles, at the insertion of which a tuft of short hairs is noticed.

The lower glume is a small triangular or ovate obtuse, acute or acuminate, one-nerved, carinate scale completely hidden in the interior of the head. The lower glume of the lowest spikelet only is larger with two or three foliaceous points turned half outside, and with its lower edge united to the back of the corresponding upper glume.

Upper glumes much larger, the largest organ of the spikelets convex outside, concave inside, broadly ovate, narrowed at base, and separated

there from one another by a deep and rounded sinus; terminating in three herbaceous, nerved, lanceolate-linear lobes, a larger central and two smaller lateral ones.

Lower palea, of course, opposite to the upper glume and therefore turned toward the center of the head, much smaller, also threepointed, with two further lateral membranaceous teeth, enveloping the upper palea.

Upper palea still smaller, two-nerved, membranaceously twopointed. Scales similar to those of the staminate flowers.

Three minute rudimentary stamens at the base of the short-stipitate compressed lenticular ovary, which at the apex bears two rather short erect styles and elongated stigmata, protruding from the apex of the flower. Hair of the stigma simple, rather short and scarcely dentate.

Mature head ventricose, thick, extremely hard, inclosing the loose grain. Grain about one line long, orbicular, ovate, flat on the outer (turned toward the lower palea and inside of the head) and convex on the inner face, two-pointed at the apex by the persistent bases of the styles. Embryo on the flat outer side of the grain and almost as long as it. Each spike or head has, with very rare exceptions, at the upper end an incomplete rudimentary spikelet, consisting of a single two to three pointed upper glume. This, with the similar looking lower glume of the lowest spikelet, seems at first glance to form an involacrum for the head; or the upper glumes together have been taken for an involucrum; the lower glumes were overlooked, and the plant placed with the panicious genus Antephora, Schreb, which is closely allied to Cenchrus. From the analysis given above, it will be seen that this view is based on a very superficial examination of our plant; and that the structure of the head is entirely analogous to that of the staminate spike of this and the spike of the chlorideous grasses in general, from which the buffalo grass can in no manner be separated.

67. MONANTHOCHLOE, Nov. GEN.-Flowers dioecious, somewhat similar. Spikelets single terminal, sessile, three to five flowered, without glumes.

Male plant.-Lower flower neuter. Lower palea foliaceous, either standing alone or with the upper palea entire, hyaline, emarginate or bilobed. The second flower very rarely with a single palea, occasionally neuter, generally horizontal. The third and also the fourth terete, elongated and staminiferous. The last flower is also abortive and reduced to a stipe with two palea. The lower palea of the staminiferous flower, is ovate-lanceolate, convolute, obtuse with a scarious

apex, growing upward, many (nine to eleven) indistinct nerves, pale beneath, coriaceous and nerveless.

The upper palea a little exceeding the inferior, convolute, obtuse with a scarious apex, two-keeled on the back, without scales. Stamens three. Anthers linear and each one deeply two-lobed, longer than the filaments, scarcely exserted. No rudiment of an ovary.

Female plant.-The spikelets similar to those of the male. Flowers generally two, more rarely one or three, fertile. The lower palea inwrapping the upper flowers of the base. Upper palea two-wingedkeeled, with wings convolute around the upper flowers, without scales, three minute rudimentary stamens. Ovary linear-lanceolate, triangular, on a narrow stem at the base, smooth, bifid, with an acute apex. Styles terminal, erect, equaling the ovarium. Stigmas as long again as the styles, exserted from the apex of the flower, plumose with simple hairs. Caryopsis free, triangular.

The grass inhabits the shores of the Gulf of Mexico, Texas and Florida. It is branching, stoloniferous and shrubby. The very short leaves are rigid and scurfy, with scarcely visible flowers.

Monanthochloë litoralis.-Perennial, shrubby, branching, stoloniferous, with smooth leaves, fasciculated, linear, sickle-shaped, short, rigid and many nerved, cartilaginous, with a somewhat obtuse apex, hairy upward to the nerves, with a rough, ciliated margin. Ligule short, truncated, with short hairs. Spikelets solitary on the top of the stem and branches, sessile within the upper leaves.

Englemann writes as follows: This peculiar and most interesting grass has been sent by Drummond from Texas, by Berlandier, from the region of Matamoras (north of the Rio Grande ?), by Blodgett, from Key West, Florida; and Lindheimer found it in flower in May, on the island of Galveston, Texas, 'covering large tracts of moist, sandy, saline soil.' I have been able to examine Berlandier's specimens, female plants in flower, and those of Lindheimer, who collected both sexes, the females more abundantly than the males. The ripe fruit is unknown to me.

Stems five to eight inches high, much branched, erect, or often at last decumbent and rooting. Upper branches mostly short, four to six lines long.

Leaves short, rarely more than three lines long, very rigid, strongly nerved, apparently permanent in winter, mostly crowded at the ends of the stems and branches. The upper leaves all bear axillary buds more or less developed. Spikelets between three and four lines long, solitary, terminal, inclosed by the uppermost leaves, which form a

complete and uninterrupted transition to the floral envelopes, the uppermost leaf, without the intercession of glumes, representing the lowest palea of the spikelet. This uppermost leaf or lowest palea has a doubtful and intermediate character, and might be taken for one or the other, or for a glume whenever it is empty; but often it includes an hyaline scale, which cannot be anything else but an upper palea, and therefore characterizes this lowest organ of the spikelet as the lower palea of the lowest always incomplete and neutral flower. It cannot be supposed that a glume is missing or abortive, as we can follow the regular succession of bud bearing leaves to this lowest floral leaf or palea. The upper palea of this lowest flower, when present, is usually extremely thin and transparent. It is small or large, flat or reflexed, nerveless or (very rarely like the other upper palea) bicarinate. It is entire, lanceolate or ovate, or emarginate, or bilobed, or sometimes divided into two unequal lanceolate parts, placed side by side, and in some flowers laterally protruding from the base of the lower palea, and rather oddly placed on both sides of the spikelet.

The second flower is like all the others, pediceled, and is mostly perfect; that is, staminate or pistillate. In a very few instances (see Fig. 271) it was found neutral, and either with a somewhat foliaceous lower palea or with both paleæ smaller than in the other flowers. Rarely it is reduced to a single palea, which is herbaceous or membranaceous. In a single instance it was almost entirely suppressed, and the third flower, above and on the same side as the lowest one, appeared to be the second. The rare case where two single empty paleæ alone are left of the two lowest flowers approaches nearest to the regular structure of the grass flowers. Those paleæ then assume the place and apparent function of glumes, and the spikelet then resembles that of Koeleria, for example, in the arrangement of its parts. The normal variability in the formation of the floral envelopes of this grass thus furnishes an interesting clue to the morphology of these organs.

The third flower, usually well developed, is sometimes (oftener in the female than in the male plant) reduced to a mere rudiment.

In female plants, I have never seen more than two pistillate flowers, and very rarely a rudimentary fourth flower; male plants show often three staminiferous flowers, usually with an upper abortive

one.

The spikelet, therefore, is destitute of glumes, and consists of three to five flowers, of which always the lowest, sometimes the second, [AG.1

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