Art. XI. Description of a New Species of Gnaphalium.
Art. XI. Description of a New Species of Gnaphalium, by Professor E. Ives.
To B. Silliman, Esq. M.D., &c.
The following description of a new species of Gnaphalium, accompanied with a drawing, has been in my possession for two years. If the subsequent observations will be of use to correct error, or solve doubts which may have existed concerning some species of gnaphalium, they are at your service.
E. IVES.
This plant was first observed by me, in company with Mr. C. Whitlow, in July, 1817, by the margin of a brook, a few rods north of Mr. E. Whitney's gun manufactory, near New-Haven. It is also found on the margin of the Housatonick, about thirty miles from Long Island sound, where it was observed by Dr. Alfred Monson, the last summer. Specimens of this plant were sent to Z. Collins, Esq. of Philadelphia, for the purpose of comparing it with the species of gnaphalium in Muhlenberg's herbarium, more particularly with the luteo-album and Pennsylvanicum, which I had not seen.
Gnaphalium decurrens.
I am indebted to the politeness of Mr. Collins, for the facts on this subject relative to Muhlenberg's herbarium. He observes, "your Gnaphalium is certainly not the luteo-album of Muhlenberg, which may not strictly be a native, but introduced. Yours most approaches G. polycephalum Mx. Still, from the decurrent leaves and other differential marks, it appears to me to be a new species. Muhlenberg's collection has it not."
As the luteo-album is said to grow in New-England, yet so far as my observation has extended it has not been found by any of the botanists, I am induced to believe that this opinion has arisen from some erroneous description of the plant which is the subject of this paper.
As the decurrent leaves of this Gnaphalium distinguish it so obviously from all the other American species of Gnaphalium, I propose to give it the specific name of decurrens.
Specific description of Gnaphalium Decurrens (large life everlasting.)
Leaves lanceolate, broad at base, acute, decurrent, somewhat scabrous above, tomentose beneath; stem leafy branched spreading, about three feet high.—See the plate.—The plate represents a section of the upper part of the plant.
FOSSIL ZOOLOGY, &c.
Art. XII. Observations on some Species of Zoophytes. Shells, &c. principally Fossil.
Art. XII. Observations on some Species of Zoophytes. Shells, &c. principally Fossil, by Thomas Say.
If the following descriptions and notices of some of the animal productions of our country, chiefly fossil, and of which some are but little known, should be found of sufficient interest to occupy a place in the Journal of Science, they are very much at your service for that work.
The greater portion of them are extracted, with some modification, from an essay which I read about three years ago, to the Academy of Natural Sciences, without any intention at the time of giving publicity to them. But the rapid diffusion of a taste for geological research, seems to require corresponding exertions on the part of those who have attended to fossil remains, inasmuch as geology, in order to be eminently furnished with every advantage that may tend to the developement of many important results, must be in part founded on a knowledge of the different genera and species of reliquiæ, which the various accessible strata of the earth present. The accessory value of this species of knowledge, is now duly estimated in Europe, as affording the most obvious means of estimating, with the greatest approximation to truth, the comparative antiquity of formations, and of strata, as well as of identifying those with each other which are in their nature similar.
Certainly very little is yet known about the fossils of North America, and very little can be known accurately, until we shall have it in our power to compare them with approved detailed descriptions, plates, or specimens of those of Europe; which have been made known to the world by the indefatigable industry, and scientific research of Lamarck and other naturalists.
America is rich in fossils. In many districts of the United States, vast beds of fossil shells, zoophytes, &c. are deposited, which, for the most part, are concealed from the inquiring eye, offering superficially a mere confused mass of mutilated fragments. These rich repositories must finally be exposed to view, by the onward pace of improvement, and the more interior strata will be unveiled by some fortunate profound excavations, the result of enterprise in the pursuit of gain. The very surface of the country in many regions, is almost overspread with the abundance of casts, or redintigrate fossils, many of which are apparently specifically anomalous, and some generically so. The correct, and only useful mode in which the investigation of our fossils can be conducted, is attended with some difficulty and labour.
The task presumes the knowledge, not only of fossils in all their different states, from the apparently unchanged specimen, to the fragment or section of a cast uninsulably imbedded in its rocky matrix, but it also requires an adequate acquaintance with recent specimens, or those of which the inhabitants are not yet struck from the list of animated beings, in other words those of the present, as well as those of the former world.
Due advantage being taken of the many opportunities which are from time to time offered to us, of obtaining knowledge in this department, will probably be the means of producing a list of American animal reliquiæ, coextensive with that of Europe at the present day. In the present state of the science, however, the correct naturalist will feel it a duty which he owes to his colaborators to proceed with the utmost caution, that he may not add unnecessarily to the already numerous species.
Genus Alveolites, Lam.
Coral lapideous, covering extraneous bodies, or in a simple mass, formed of concentric strata; strata composed each of a union of numerous alveoles, which are very short, contiguous, reticulate, and generally parallel.
Species.
A. glomeratus, alveoles vertical, subequal, oval, or obsoletely hexagonal, much shorter than the diameter, parallel; paries simple; strata numerous, forming a rounded mass. (Cabinet of the Academy of Natural Sciences.)
Found often on the coast of North America, cast up by the waves, the animals sometimes still living. Forms masses of various sizes and figures, generally more or less rounded or lobed, and composed of a great number of concentric layers. The number of these strata seems to be regulated in some degree, by the quantity of surface they have to cover. Thus if the nucleus happens to be a small shell, such as the Naticæ, Nassæ, &c. of our coast, or even the oyster, (O. virginica,) clam, (V. mercenaria,) &c. the strata are often very numerous; but on the thoracic plate of Limulus polyphemus, having a considerable space over which to extend themselves, the strata are but few, not more than 2 or 3. I have seen the thoracic plate of this animal so entirely covered by the Alveolite, as to have the eyes and stemmata concealed so as to be perfectly blind. When composed of a single layer only, it much resembles a Flustra, or a Cellapore of which the convex surfaces have been removed by attrition. The animal I have not yet examined. The alveoles or cells of a layer, are arranged in lines of different degrees of curvature, obscurely radiating from different centres; these lines are placed side by side, the alveoles alternating with each other throughout the layer in a quincunx manner; the thickness of the paries is somewhat equal to one half of the conjugate diameter of the alveole, the length of which, or thickness of the layer, is scarcely more considerable; but these proportions vary.
The species to which it seems allied, are madreporacea and incrustans. The former is fossil, and differs in being subramose; the latter forms but a single expansion.
Genus Favosites, Lam.
Coral lapideous, simple, of a variable form, composed of parallel prismatic and fasciculated tubes; tubes contiguous, pentagonal, or hexagonal, more or less angular, rarely articulated.
Species.
F. striata, more or less turbinate; paries of the alveoles longitudinally striated within, and fenestrate with minute osculi; alveoles with very numerous septæ. (Cabinet Acad. Nat. Sciences; and Peale's Museum—common.)
Found fossil in various parts of the United States, at the falls of the Ohio; Genessee, New-York; Pittsburg and Wilksbarre, Pennsylvania; Missouri, &c. &c. but not yet in the alluvial deposit of New-Jersey.
The tubes are generally, partially, or entirely filled with silicious matter, sometimes so completely so, as to resemble in miniature, basaltic columns; when the alveoles are free on the surface, these fossils are known by the name of petrified wasp-nests, from the resemblance they bear to the nests of those insects. The silex is usually only infiltrated into the cavities, leaving the substance of the coral in its original calcareous state, but the specimens which are found amongst the rolled pebbles of the Delaware River, near Philadelphia, are completely silicified.
The size varies from one fourth of an ounce, to two hundred pounds or more, and the tubes occur of every intermediate diameter, from the fortieth to one fourth of an inch. It is not common to find any two specimens of like form, they are, however, ordinarily more or less turbinate, but are sometimes depressed or compressed, and the tubes rectilinear or excurved, and of various lengths. The dilated summit is not so much the effect of a gradual enlargement of the tubes, as of the frequent and adventitious interposition of young ones, which of course renders the openings of the tubes unequal. The tubes or alveoles, vary in the same coral, being 5 or 6, rarely seven sided, but the hexagonal form is most common; the interior of a tube is divided into a great number of apartments or cells, by approximate transverse septæ, each of the cells appears to be connected with the corresponding cells of the surrounding tubes, by lateral orifices in the dividing paries; these orifices are minute, inequidistant, orbicular, their margins slightly prominent, and forming from one to three longitudinal series on each side of the tube; each row is separated from the adjoining one by an impressed line. By means of these osculi it seems probable that all the animals inhabiting a common coral, were connected together, or had free communication with each other, but whether by means of a common organ as in Pyrosoma, Stephanomia, &c. or simply by contact as in the aggregating Salpa, &c. we have no means of determining.
The striata differs from Madrepora truncata, Esper. (F. alveolata, Lam.) in not being "extùs transversè sulcata." It seems to be allied to Corallium Gothlandicum, Amœn. Acad. v. 1. p. 106, and it is possible it may prove synonymous, or very similar to it, when that species becomes better known; the latter has been taken for Basalt, and M. Lamarck when describing it, inquires "Est-ce un polypier?" Madrepora fascicularis, of Volck. and Parkin. in common with F. striata and F. Gothlandicum, is distinguished by the transverse septa, a character which induced me to refer the species here described to Favosite; they seem therefore to be congeneric, as analogy indicates a participation in the character of osculated paries.
Amongst the great variety exhibited by this species, we have to remark more particularly the following, viz.:
1st. Alveoles perfectly free, that is, destitute of aciculi or lamellæ, the septa wanting, and sometimes the osculi obsolete.
2d. Alveoles filled almost to the summit with the septa, and resembling those combs of the bee-hive which are filled with honey and covered over.
3d. Paries beset with very numerous, interrupted, alternating, transverse lamellæ, which are denticulated at their tips, and project towards the centre with various degrees of prominence and irregularity.
The first variety corresponds with the generic character, and the third approaches the genus Porites; yet so unequivocally identical are they, that I have seen them all united in the same mass, and perforated throughout by the osculi. The identity is further obvious by the perfect gradation which renders them inseparable.
With respect to the transverse septa, I think their presence may be accounted for by supposing that as the animal elongates its tube in consequence of an increase of growth, or in order to maintain an equal elevation with the adjacent tubes, (rendered necessary by the origin of young tubes in the interstices) it gradually vacates the basal portions of its tube, and sustains itself at the different elevations, by successively uniting the parietal lamellæ so as to exclude the vacuity. That this is probable, we may infer from a similar procedure on the part of several species of testaceous mollusca. Thus some Linnæan Serpula become camerated, and a familiar instance presents itself in the Triton tritonis, the animal of which adds successive partitions to the interior of the spire, as that part becomes too strait for the increasing volume of its body. If the above supposition proves correct, the organs of communication which pass through the osculi, can hardly be in common, but must rather connect the animals by simple contact only, otherwise these parts would be broken when the animal changes its place by vacating the inferior part of the tube.
The third variety is then the state of that portion of the tube which is inhabited by the body of the animal, and not yet interrupted by the septæ.
From the above observations, it is evident that this species, and probably the entire genus Favosite under which I have placed it, will not arrange properly with the Tubipores, Millepores, &c. but must be transferred to the Polypiers Lamellifères of Lamarck. And if the Madrepora retepora of Solander and Ellis, is a true Porites, as M. Lamarck supposes it to be from the appearance of its tubes, I should conclude this genus to be very proximately allied to Favosites, by that species and the F. striata having in common the remarkable character of fenestrated paries. But to this character I should conceive a generic importance ought to be attached, as indicating a differential organization of the artificers. I have no doubt that on close inspection of a perfect specimen, the same character will be found to exist in F. Gothlandicum, and possibly also in F. truncata, if not in the latter only, it may be proper to separate the genus and to withdraw from Porites the forementioned species, retaining to striata as specifically essential, the second member of the differential description.
(To be continued.)
PHYSICS, CHEMISTRY, &c.