1422

ARBORETUM AND FRUTICETUM.

PART III.

other masts, or acorns ; the only species that was known to the Romans having been the./dglans regia, or common walnut tree.

Description. Large trees, with pinnate leaves, coarse-grained wood, andfruit, in one species at least, much esteemed at the dessert, and valuable for theoil which it contains.

General Observations. The trees belonging to this order bear, with onlytwo or three exceptions, so close a resemblance to one another in theiryoung state (in which state alone most of them are to be seen in Britain ),that we have been unable to satisfy ourselves as to what are species, and whatare only varieties. In pursuance of our idea, that no plant can be truly aspecies, that is not readily distinguished from every other, in every stage of t

its growth, and at every season of the year, we should say that there werenot' more than two species of walnut hitherto discovered, either in Europe orAmerica ; viz. Jiiglans regia and ./. nigra: and three species of Carya; viz. C.amara, C. laciniosa, and C. squamosa. We submit this opinion, however, withgreat deference, having formed it chiefly from inspecting the young plants in theHorticultural Society’s Garden, in the collection of Messrs. Loddiges, and fromobserving the great variety of foliage distinguishable in a bed of seedlings of anyof the American sorts; we shall therefore adopt the descriptions and figuresof Michaux, and leave the truth to be discovered by time and future observa-tion. Previously to describing the species of the three genera, .7uglans, Carya,and Pterocarya, we shall quote Michaux’s introductory observations; pre-mising that this author includes both JDglans and Carya under the genus./uglans; the genus Carya, as we have seen in the generic characters above,having been separated from Jtiglans by Nuttall, chiefly on account of a tech-nical distinction in the fruit. “ The walnuts of North America, ” Michaux ob-serves, “ appear to present characters so distinct, as to require their division /into two sections. These characters consist principally in the form of the bar-ren aments, or male catkins; and in the greater or less rapidity of growth in the j

trees. The first section is composed of walnuts with single aments, and in- |

eludes two American species: the black walnut (Jiiiglansnigra L., fig.1260. inp.1436.), and the butter-nut (./. cinereaL., fig.1262. in p.14.39.); to which isadded the European walnut (./. regia L., fig. 1257. in p. 1425.). The secondsection consists of such as have compound aments, and comprises eight spe-cies : the pacane-nut hickory (Carya olivasformis Nutt., fig. 1263. in p. 1442.),the bitter-nut hickory ( C. amara Nutt., fig. 1264. in p. 1443.), water bitter-nut hickory ( C. aquatica Nutt., fig. 1265. in p. 1444.), mocker-nut hickory( C. tomentosa Nutt., fig. 1267. in p. 1445.), shell-bark hickory ( C. 61baNutt., fig. 1269. in p. 1446.), thick shell-bark hickory (C. sulcata Nutt.,fig. 1271. in p.1449.), pig-nut hickory (C. porcina Nutt., fig. 1273. in p.1450.),and nutmeg hickory (C. myristicaeformis Nutt., fig. 1275. in p.1451.). The firstthree species of the second section bear some relation to those of the firstin their buds, which are not covered with scales. For this reason, I have jplaced them immediately next, beginning with the pacane-nut hickory, which,by its numerous leaflets, most nearly resembles the black walnut and thebutter-nut, the buds of which are also uncovered. Throughout the UnitedStates , the common name of hickory is given to all the species of the secondsection. This common appellation is due to certain properties of theirwood ; viz. coarseness of grain, and a reddish colour in the heart-wood,which, however modified, are possessed by them all, in a greater degree thanby any other tree of Europe or America . These species exhibit, also, a '

striking analogy in their forms and in their leaves, though they differ in the ,

number and size of their leaflets. To these sources of confusion must beadded another in the fruit, which is often so various in its appearance, that itis easy to mistake the species to which it belongs. It is not, then, on themost remarkable differences alone that our distinctions must be founded;recourse must also be had to an examination of the shoots of the precedingyear, of the buds, and of the aments.” ( Michx. North Amer. Sylva, vol. >•p. 139.)