53 Erysimum officinale. Westward, preceding cultivation, in great quantities. 54 Sonchus oleraceus. Every where. 55 Cnicus lanceolatus. Far surpassing in quantity and dissemination any native species of Cnicus. 56 Carduus arvensis. Not farther south than New Jersey. 57 Arctium Lappa. Every where. 58 Chrysanthemum leucanthemum. Rapidly advancing westward, where eight years ago it had not made its appearance. 59 Anthemis cotula. Decidedly the most universal of our gregarious plants. In the west and south it precedes cultivation. 60 Achillea millefolium. Every where. 61 Urtica urens. Very generally spread. 62 Urtica dioica. Do. do. 63 Lithospermum arvense. Very generally. II. Plants but partially spread. 64 Fedia olitoria. Tennessee and Carolina, in some localities. 65 Agrostis spicaventi. New England and Carolina, in some locali 66 ties. Arrhenatherum avenaceum. Tennessee and Carolina, do. 67 Dactylis glomerata. New Eng. Tennes. Carol. do. 68 Alopecurus pratensis. New England-not widely spread. Do. 70 Lolium temulentum. New England and Tennessee. 71 Setaria viridis. Here and there northwardly. 74 Briza media. New England. 75 Blitum capitatum, New England and New York. 76 Blitum virgatum. } 77 Galium verum. New England. 88 Echium vulgare. Spread beyond the Susquehannah. 79 Anagallis arvensis. Northwardly. 80 Verbascum Lychnitis. About Philadelphia. 81 Hyoscyamus niger. In the eastern states. 82 Solanum dulcamara. Sparingly in the northern states. 83 Bupleurum rotundifolium. Here and there in Carolina, occupying whole fields. 84 Chenopodium urbicum. Northern states. 85 86 rubrum. New England and New York. 87 Conium maculatum. Here and there in the northern states. 88 Ornithogalum umbellatum. Spreading greatly in the northern states. 89 Polygonum orientale. Southward and westward. 90 Saponaria officinalis. Here and there-common. 91 Spergula arvensis. Northern states. 95 piperita. In Carolina, here and there. 96 Thymus serpyllum. In Pennsylvania, common. 97 Melissa officinalis. Here and there. 98 Lepidium officinale. Pennsylvania. 99 Thlaspi arvense. In many localities. Do. 101 Sisymbrium officinale. Do. 102 Malva rotundifolia. Very rarely southward-common northward. 103 Fumaria officinalis. Very confined localities-Carolina. 104 Genista tinctoria. New England. 105 Vicia sativa. Here and there. 106 Melilotus officinalis. Do. 107 Trifolium procumbens. Very common southward, and beginning to become universal. 108 agrarium. Confined to localities northward. 109 Medicago lupulina. Near Carlisle and other localities. 110 intertexta. Southwardly only. (S. Carol.) 111 Cichorium intybus. Northwardly, in some localities. 112 Apargia autumnalis. New England. 113 Sonchus arvensis. Do. 114 Cynara scolymus. Virginia. (Nuttall.) 115 Inula helenium. Along the Ohio hills in great quantities, and elsewhere, here and there. 116 Senecio vulgaris. New York and New England. 117 Euphorbia helioscopica. Shores of Lake Erie and elsewhere. 118 Amaranthus Blitum. Northwardly. 119 Xanthium spinosum. Southwardly, as far as Washington. III. Introduced only in the vicinity in which they are or were cultivated. 120 Ligustrum vulgare. 121 Syringa vulgaris. 123 Nicotiana rustica. 124 Periploca græca. New York. 125 Chenopodium bonus henricus. 126 Hemerocallis fulva. 127 Tanacetum vulgare. 128 Achillea ageratum. North Carolina, in some localities. 129 Tussilago farfara. Pennsylvania. 130 Helianthus tuberosus. Pennsylvania and Carolina. 136 Prunus spinosa. New England. 137 Dipsacus sylvestris. Pennsylvania. No Scabiosa, no Viola, no Papaver, and no other segetal plants occur at all naturalized. The Bellis perennis, so universally disseminated in Europe, is never seen. None of the shrubs usual in hedge-rows, have become naturalized. It is particularly remarkable, that the Centaurea cyanea, though very frequently cultivated for ornament, in the gardens of the German farmers in Pennsylvania, has never spread into grain fields, in which it is so prevalent in Europe. This is likewise the case with Delphinium consolida and many others; while the introduction into a garden in North Carolina of Antirrhinum linaria, and of Stellaria media, in a very few years contaminated the whole vicinity for many miles. The readiness with which plants like Leontodon taraxacum, Cnicus lanceolatus, &c. with feathered seeds spread, is easily conceived. Not so readily explained is the cause which renders Anthemis cotula so wonderfully prevalent. In the mean time it is observable. that a large river is apt, as well as a tract of land intervening entirely unsuited to the growth of some of these emigrants, to stop their progress for a time. But when once the passage is forced at any point, the dissemination appears to proceed the more rapidly. In 1823, the Anthemis arvensis, or cotula, in Tuscarawas county, Ohio, had widely spread up to the eastern bank of the Muskingum or Tuscarawas river, but had not crossed to the western bank. In 1831 I met with it, in incredible quantities, every where. The circumstances which prevent some plants, that are naturalized to a great extent in certain localities, from extending generally, are often not to be discovered. Thus, for fifty years at least, Cichorium intybus is as much spread in the vicinity of Bethlehem as any native plant; while I never saw it westward of the Susquehannah, nor in this neighbourhood at any considerable distance from the town. The worst enemies of the farmers, at least in the northern states, are all foreigners; on which account we have reason to congratulate ourselves, that no greater number of these foreign weeds are prone to usurp the soil; for it is certainly worthy of remark, that among upwards of four thousand species of plants in the United States, not more than from 120 to 130 foreigners should have obtained any thing like a permanent and extensive footing. The following few plants, in some degree naturalized in the southern states, are not derived from Europe: Polycarpum tetraphyllum. Leucas martinicensis. Cucurbita lagenaria. OBSERVATIONS on a Fossil Jaw of a species of Gavial, from West Jersey. By J. E. DEKAY. Read January, 1833. IN a paper which I had the honour to lay before the society some time since, the attention of the members was called to some fossil remains from the southern parts of New Jersey. The interest which has been excited, both here and in Europe, on this subject, induces me to submit a few additional observations on some organic remains from the same locality. For the opportunity thus afforded me I have to express my obligations to Lieut. Mather, of the army, who has kindly placed the specimens in my hands for examination. A few brief remarks upon the region from whence these and other remains are found in such abundance, may be necessary previous to describing the fossils themselves. West Jersey, or that part of the state of New Jersey which lies south of a line drawn from Trenton to Amboy, is composed entirely of sand, passing at some places into gravel. At the Highlands of Navesink, which rise into hills 300 feet high, a rock formation appears, containing fossil shells and crustacea. This same rock appears on the borders of a stream at Tinton Falls, and from its composition is called ferruginous sandstone. It consists of iron and silex with potash and alumine; and the same materials, in various proportions, compose those numerous local deposits which are found extensively scattered over this whole region. To some of these are applied the name of marle pits, on account of their fertilizing properties; although totally dissimilar to the marle of Europe; and, in fact, only acting mechanically, like any other clay, when mixed with a sandy soil. In these various deposits are found animals of fresh and salt water, of such as were formed to encounter the |