Part 14

Genus Brongniatia--Fore abdomen always, and post abdomen in some cases, longitudinally divided into three lobes, by regular series of undulations traversing the joints, without grooves; articulations of the side lobes being manifest continuations of those of the middle lobe, and consequently, agreeing in number.

Brongniatia Platycephala. Eaton.

Head and fore abdomen very broad and depressed, the abdomen with ten joints curved forwards at the undulations; post abdomen and tail with about fifteen joints curved backwards at the undulations; the three lobes of the tail more distinctly separated; divisions between the joints of the abdomen double.

The representation of B. platycephala, figure 20, plate 2, of the Geological Text Book, if it be accurately drawn, is certainly of a trilobite never before described. On the buckler, which is without eyes, there is delineated a figure, not unlike some of the leaves of the mulberry tree.

The tail is also very peculiar. In Silliman's Journal, Volume 21st, page 136, Professor Eaton proposed for this curious fossil the temporary name of Ogygies latissimus. It is found, he observes, "in the upper soft slaty variety of the rock which has been so successfully used for the lias cement at Chitteningo, &c. Dr Smith, of Lockport, (N. Y.) sent me two specimens, taken from a continuation of the Chitteningo lias rock, immediately beneath the geodiferous lime rock on which the cherty (cornitiferous) reposes." The whole animal is six inches long, and three broad.

Nature of the Trilobite.

Every one familiar with the history of the Trilobites, is aware that a good deal of controversy has existed among naturalists, respecting the precise link in the grand chain of organized beings, these singular fossil animals, should occupy. Professor Brongniart, Dr. Dekay, Audoúin, and several other acute observers, have placed them in the vicinity of the Limuli, and other Entomostraca with numerous feet; while P. A. Latreille and others, presuming that these animals were destitute of locomotive organs, as no vestige of them has ever been discovered, fix their natural position in the neighbourhood of the Chitones; or rather that they constituted the original stock of the Articulata, being connected on the one hand with these latter Mollusca, and on the other with those first mentioned, and even with the Glomeris. It was our original intention to have closed this Monograph with a short history of these theories--and of the notion advanced by Latreille and others, that the Trilobites have been annihilated by some ancient revolution of our planet. All these matters, we think, are now put to rest by the late discovery of some living Trilobites in the southern seas, near the Falkland Islands. In the cabinet of the Albany Institute, we have examined some of these recent animals, which have very nearly the size and general appearance of the Paradoxides Boltoni, as represented on our frontispiece; the species cannot, however, belong to that genus, as the buckler is furnished with eyes very similar to those of the Calymene Bufo; its organs of locomotion are short, numerous, and concealed under the shell--but I do not feel at liberty to notice the interesting animal more minutely. It will probably be described and figured shortly, in a perfectly full and satisfactory manner, by Dr. James Eights, the enterprising discoverer, together with several other new and remarkable genera and species belonging to the Entomostraca.

FINIS.

Index to the Species. ————

CALYMENE Blumenbachii, page 28 Callicephala, 30 Selenecephala, 31 Platys, 32 Microps, 34 Anchiops, 35 Diops, 37 Macrophthalma, 39 Bufo, 41 Rana, 42 ASAPHUS Laticostatus, 45 Selenurus, 46 Limulurus, 48 Caudatus, 50 Hausmanni, 52 Pleuroptyx, 55 Micrurus, 56 Wetherilli, 57 PARADOXIDES Boltoni, 60 OGYGIA Sillimani, 63 ISOTELUS Gigas, 67 Planus, 68 Cyclops, 69 Megalops, 70 Stegops, 71 CRYPTOLITHUS Tessellatus, 73 Bigsbii, 76 DIPLEURA Dekayi, 79 TRIMERUS Delphinocephalus, 82 CERAURUS Pleurexanthemus, 84 TRIARTHRUS Beckii, 87 NUTTAINIA Sparsa, 89 BRONGNIATIA Platycephala, 91

JOSEPH BRANO,

No. 12, CASTLE STREET, PHILADELPHIA,

Teacher of the Art of Preparing Birds, Quadrupeds, Reptiles, &c. &c.

AND OF THE

Art of making Moulds and Casts in Wax, Plaster, and Compositions.

In addition to the casts taken from the originals of the Trilobites, he has also a few fine casts of the bones of the Megalonix Laqueatus, Harlan.--Scaphites Cuvieri, Morton.--Mosasaurus tooth, and of several rare fossil American Plants;--all taken from the original fossils, in the Cabinet of the Academy of Natural Sciences, &c. &c. These models are fac similes of the real objects, coloured according to nature.

As the originals of the above are in the possession of different public and private cabinets throughout the United States, I have at great trouble and expense, taken from them exact patterns, so as to accommodate museums and scientific gentlemen with them on very reasonable terms. This practice is now used in several parts of Europe; and thus the curious are able to supply their cabinets with rare specimens, often superior to the originals.

·—▸⏵►●◓●◄⏴◂—·

JOSEPH BRANO having finished for us a number of models of different objects in Natural History, we have no hesitation in recommending him as an exceedingly skilful artist.

Jacob Green, M. D. Rich'd. Harlan, M. D. P. A. Browne, ESQ. Chas. A. Poulson. Isaac Parrish, M. D. S. G. Morton, M. D.

Philadelphia, October 3d, 1832.

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Transcriber Note

Minor typos corrected. The quotation on page 91 has been corrected based on the original article found at The Internet Archive.