NATURAL SCIENCES OP PHILADELPHIA. 187 heavy, and are very pilose. The eyes are large and very prominent. The dorsum is slightly convex, and is ornamented on each side by a broad fuscous stripe, which is intersected by numerous, indistinct, dark lines. The scuta are very smooth, and have no distinct lateral plates, but their edges are rather thin and strongly elevated. The penultimate scutum is much broader than its neighbors. The last scutum is very small. The feet are dark colored. There are two or three specimens in the possession of the Academy, which, I believe, were collected by Dr. John L. Le Conte, U. S. A., in the moun-tains of Georgia. Family BIPUONOPHORIDJE. Genus BRACHYCYBE. Rostrum acutum, brevissimum, antennis multo breviore. I have never studied the allied genus Siphonophora of Brandt, but, if the characters relied on by that author are at all generic, there can be no doubt that the American species belongs to a distinct genus. In the Siphonophora the rostrum or mouth is very much elongated, and approaches the antennae in length. In Brachycybe the latter are several times the longer. B. leconth, Wood. Fulvo-brunneus? dorsomodice convexo, medio leviter canaliculato; antennis parvis, filiformibus, pilosis ; scutorum superficie asperata, obscure transverse canaliculata ; scuto postremo postice spina? obtusse serie instructo ; laminis lateralibus longis, angustis, vix sejunctis ; segmentis 47 ; pedibus breve pilosis. In our specimens, which have been preserved for a long time in alcohol, the color is a light yellowish-brown. The anterior scuta are tuberculate, the pos-terior merely roughened. Each has a more or less obsolete transverse groove extending along the lateral lamina. The latter are very long and narrow ; they are placed very close together, and are often bent slightly backwards. Their external margin is somewhat oblique, and is furnished in all except, perhaps, the most anterior, with a pore. The small feet are entirely concealed beneath the broad body. The male genital appendages consist of two pairs of acute feet-like processes. It affords me much pleasure to dedicate this species to Surgeon John L. Le Conte, U. S. A., as an acknowledgement of the many as-sistances which he has afforded me in the prosecution of my studies. Ilab. Georgia. Coll. of the Acad. Alus. Comp. Zoology. Dr. John L. Le Conte, U. S. A. Note on the PARALEPIDOIDS and MICROSTOMATOIDS, and on some Pecu-liarities of Arctic Ichthyology. BY THEODORE GILL. My attention having been attracted to the resemblance between the Alepido-sauroids and Paralepidoids, shortly after my article on new species of the former family, I embraced the oppjrtunity, when in Philadelphia, to examine the specimens of the two genera, 1'aralepis and Sudis, in the Bonaparte col-lection, secured by the liberality of Dr. Wilson. The suspicions of the close affinity of the two families were fully confirmed, and the same logic that would prove the Alepidosauroids to be Siluroids, would cover the Paralepidoids. Nearly equally erroneous would be the reference of those families to the Scom-broid group, near which I formerly retained it with Lowe. The Paralepidoids are, indeed, chiefly distinguished from the Alepidosauroids by the small dorsal fin, and the more posterior ventrals, and wherever one is placed, the other must be approximated next to it. The species of this family of Paralepidoids are divisible among three groups, 1864.]
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