The genus Saxe-Gothæa forms a transition of the most remarkable kind from Conifers to Taxads. Sir William Hooker regarded it as a Podocarp with flowers in a cone. It is in reality a genus with the male flowers of a Podocarp, the females of a Dammar, the fruit of a Juniper, the seed of a Dacrydium, and the habit of a Yew.

The timber of the Zadd or Théda of Abyssinia, Juniperus procera, one of the largest trees of that country, is hard, durable, and much employed in construction there. It is very nearly the same, if really different, as Juniperus phoenicea.-A ch. Rich.

That the plants of this order are sometimes poisonous, like Taxads, is now certain. Two children were poisoned a few years since at Chichester, from swallowing the leaves of what was called at the inquest Male Cypress, but which I ascertained, from evidence furnished by Mr. Buckell, to be Cupressus Thyoides.

Fig. CLVIII. a.-Cone of Pinus muricata, showing the difference between the outer and inner sides of the same strobilus when the inner side is pressed against a branch. 1. A pair of leaves; 2. the end of the leaf magnified; 3. a seed, natural size.

Fig. CLVIII. b.-Saxe-Gothæa conspicua; 1. male spike; 2. anther; 3. scale of galbulus with ovule; 4. ripe galbulus.

Taxineæ, Rich. Conif. 124. (1826); Bartl. Ord. Nat. 95. (1830); Martius Conspectus, No. 58. (1835); Endl. Gen. lxxviii.; Meisner, p. 353.-Taxaceæ, Ed. pr. (1836).

DIAGNOSIS.-Gymnogens with repeatedly branched continuous stems, simple leaves often fork-veined, solitary females, 2-celled anthers opening longitudinally, and the mem

brane next the nucleus inclosed.

Trees or shrubs with continuous, unarticulated branches. Wood having the ligneous tissue marked with circular disks. Leaves usually narrow, rigid, entire and veinless, evergreen, alternate or distichous; sometimes dilated and lobed, and in those cases having forked veins of equal thickness. Flowers 9, naked, but surrounded by imbricated bracts. Stamens several; filaments usually monadelphous; anthers combined or distinct, opening longitudinally. solitary. Ovules naked, the foramen at their apex, their outer skin becoming finally hard. Seed usually supported or surrounded by a succulent imperfect cup-shaped pericarp. Albumen fleshy. Embryo straight, dicotyledonous, either antitropal or orthotropal.

Fig. CLX.

Yews are separated from Conifers by their fruits not being collected in cones, each ovule growing singly, unprotected by hardened scales; so that this is a degree of organization yet lower than that of Conifers themselves. It is also to be observed, that in this Order the leaves do not always preserve the veinless needle-shaped state of Conifers, but expand and form veins, which are then forked and of uniform thickness, just as in Ferns. To me it appears that this deviation on the part of many genera from the Coniferous form of fruit, is a good practical distinction. Mr. Bennett, however, is of opinion that Taxads should not form a distinct Natural Order, but ought to be associated with Conifers; at least such I presume to be the bearing of his observations in Horsfield's Planta Javanica, p. 37. In the opinion of this excellent botanist, Taxus belongs to Cupresseæ, while Podocarpus and Dacrydium should be associated with Abieteæ, an opinion to which he seems to be led, in part at least, by considerations connected with the pollen of those plants. What these peculiarities of the pollen are, is explained at p. 228. But I see no reason why two kinds of pollen should not be comprehended under the Order of Taxads as well as under Conifers; and the importance of distinctions in the pollen of plants appears to me to be at least very doubtful.

Fig. CLIX.-Taxus baccata loaded with male flowers; 1. a male flower; 2. an anther; 3. a female flower: 4. a vertical section of an ovule; 5. of a ripe fruit: 6. of a ripe seed, showing the embryo.N.B. 4. and 6. are the same part in youth and age; 5. is the ripe ovule, with an accessory cup

Fig. CLX.-Perpendicular section of the ripe fruit of Taxus, together with the cup-shaped pericarp, which rises round it after the pollen has taken effect upon the ovule.

These plants occur in the milder climates of a great part of the world, and hence they are found in elevated situations within the tropics. The common Yew is the only species known in Europe; and it is common in the North of Asia. The majority belong to Asia or its dependencies. Dacrydium and

Phyllocladus are abundant in New Zealand. Of Podocarp, the richest of any in species, three are found at the Cape of Good Hope.

Yews and their allies are resinous like Conifers, and often valuable for their timber, as evinced by the common Yew, which is unsurpassed for durability and elasticity. Podocarpus cupressina (Chomoro) is one of the best timber trees of Java. The Dacrydium taxifolium, or Kakaterro of New Zealand, acquires a height of 200 feet.-Ed. Ph. Journ. 13.378; its branches may be manufactured into a beverage resembling in antiscorbutic qualities the well-known spruce beer. Podocarpus Totarra furnishes the most valuable timber in New Zealand; and it is said that the possession of the trees has been the cause of wars among

the savage natives. The leaves of the common Yew are fetid, very poisonous, especially to horses and cows. (Rex Cativolus Taxo, cujus magna in Gallia Germaniaque copia est, se exanimavit. Cæsar.) The berries are not dangerous. The seeds are said to be unwholesome. On the authority of an Italian physician it is stated that Yew-leaves, when admimistered in small doses to man, have a power similar to that of Digitalis over the action of the heart and arteries, reducing the circulation, and if persisted in too long, or given in too large doses, as certainly fatal. Yew is, however, reported to have one decided advantage over Digitalis, by its effects not accumulating in the system; so that it is a much more manageable and more efficient remedy.-Burnett. The bark of Phyllocladus trichomanoides yields a red dye. The fruits of Salisburia, a tree of great beauty, now common in Europe, are about as large as Damsons, and both resinous and astringent; their kernels are thought by the Japanese to promote digestion. The nuts of Caryotaxus are very astringent, and are employed by the Japanese interpreters, "ad coercendam urinam," when they are likely to be detained for a long time in the Imperial Council Chamber.

Fig. CLXI.-Phyllocladus rhomboidalis; 1. a spike of ; 2. an anther, 3. the inflorescence of the

, with a pair of flowers.

ORDER LXXVI. GNETACEE.-JOINT FIRS.

Gneteæ, Blume, in Ann. Sc. 2. Ser. 2. 105. (1834).-Gnetaceæ, Lindl. in Bot. Reg. 1686. (July, 1834); Endl. Gen. lxxix.; Meisner, p. 352.

DIAGNOSIS.-Gymnogens with repeatedly branched jointed stems, simple net-veined leaves, 1-celled anthers opening by pores, and the membrane next the nucleus protruded. Small trees very much branched, or sarmentose shrubs, secreting watery, not resinous

1

Fig. CLXII.

Fig. CLXIII.

matter, with opposite or clustered branches, and thickened separable articulations. Leaves opposite, entire, with anastomosing, reticulated veins; sometimes very minute and scale-shaped Wood with the ligneous tissue marked with circular disks. Flowers, arranged in catkins or heads, surrounded by opposite decussating scales which are connate at the base, or altogether consolidated into a horizontal ring. Calyx 1-leaved, transversely slit at the end, projecting from its bottom a monadelphous filament bearing 1-celled anthers, bursting longitudinally and centrally, so as to form a pore. Pollen (in Gnetum, simple, smooth, oblong, Griffith), in Ephedra ellipsoid, with 6 longitudinal furrows. altogether naked, or sheltered by a false calyx consisting of two scales, more or less combined, each of which surrounds one or two flowers. Ovary 0. Ovule pointed by a style-like process formed from a third membrane surrounding the nucleus. Seed drupaceous, before maturity pierced at the point and terminated by a style-shaped protruded process; finally pointless. Seed-coat thickish, either altogether leathery, or shelly, or fibrous internally, and succulent externally; in Gnetum lined by acicular woody tissue. Embryo dicotyledonous, in the middle of fleshy albumen; radicle superior.

Conifers and Cycads present features so peculiar that their separation from all other Orders is a point concerning which there can be no difference of opinion. It is indeed difficult to trace a plain transition from them to the other parts of the Vegetable Kingdom in which perfect sexes are present. There exist, however, a few plants, not very similar to each other in appearance, bearing the names Gnetum and Ephedra, in which we find precisely the structure and habit that would be wished for by a theorist searching for evidence to bring Gymnogens into communication with true Exogens; for one of them has all the appearance of a Chloranth, and the other of a Casuarina; and yet both retain the true peculiarities of Gymnogens. These are called Gnetaceæ, and may in English be termed Joint Firs, for they are closely allied to Conifers, but are distinctly known by their stems being jointed at every node. In these plants there is little tendency to form cones, and in the genus Gnetum the development of the ovule is so peculiar that botanists at one time, myself included, supposed that the real ovule was in truth an ovary pierced at the summit, for it consists of an exterior shell of considerable thickness and of a green colour; within which is a thinner envelope through which passes a tubular projection fringed at the point, and within these lies a nucleus, as is represented in the accompanying figure of the young ovule of Gnetum Brunonianum, copied from an unpublished drawing by Mr. Griffith. So that this sort of ovule has 3 distinct integuments, clear of the nucleus. It is to Mr. Griffith that I owe the knowledge of the true nature of these plants. In a most elaborate unpublished Memoir

Fig. CLXII.-Gnetum Gaemon: 1. a section of an ovule showing the three membranes, of which the innermost protrudes in the form of a stigma.

Fig. CLXIII.—A thin section of the wood of Gnetum Gnemon, highly magnified, after A. Brongniart