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XEROBATES ORTHOPYGIUS, sp. nov.

This large land-tortoise is represented by numerous remains in my possession. One of these includes the greater part of the entire animal, exhibiting, besides the shell, the limbs and a perfect skull, with mandible. The specimens were obtained by an expedition which explored the fossiliferous Loup Fork beds of Kansas, in charge of R. S. Hill.

The genus Testudo, as left by Gray in the "Catalogue of Shield Reptiles", embraces two genera. To one of these Agassiz gave in 1857 the name of Xerobates, with a diagnosis. In 1869, Gray characterized the two forms quite exactly (see his "Supplement to the Catalogue”, etc.), but retained the name Testudo for Agassiz's Xerobates, and gave Agassiz's Testudo another name (Peltastes). As Xerobates was first proposed, it is here retained.

This species has numerous peculiarities. The most striking is the form of the posterior free border of the carapace. Instead of being rounded, it is transverse, presenting a rounded lateral angle on each side. The marginal bones of this transverse portion are vertical, extending below the line of the lateral free marginals, and their edges are very little recurved, although acute. The free marginals in front of the latero-posterior angles are not recurved, but are obtuse and somewhat incurved, presenting an abrupt contrast to the median marginals; the whole arrangement of the free border thus differing from anything which I have heretofore observed in this genus. The sides of the carapace swell outward, and the scutal sutures are well marked.

The plastron is a little concave, and has thickened borders. These have the peculiarity of rising with a vertical external face to meet the inner inguinal and axillary buttresses of the carapace. There is no transverse buttress or septum in this part of the plastron, and but a slight one on the carapace. The postabdominal bones are not prominent, but are simply emarginate. On the other hand, the clavicular (episternal) bones are produced into a flat beak, which is not emarginate, but truncate in front. It is thickenod backward, and encloses a deep fossa with the succeeding portion of the plastron. The pectoral scuta are exceedingly narrow, and the humero-pectoral dermal suture turns forward to the axilla. The general surface is without sculpture.

There are numerous osseous bosses on the limbs, doubtless ossifications of large marginal and other dermal scuta. They have usually a low apex, central or eccentric.

The maxillary alveolar border is rather finely serrate, and the two inner alveolar ridges are rugose. The premaxillaries are not prominent, and are separated by a slight notch. The cranium is of medium proportions, and neither elongate nor widened. The profile is plane, except a slight descent to the nares. The zygomata were probably complete, but slender. They are broken off in the specimen, but preserved loose. There is a fossa at the base of each exoccipital, and a wide one on the basioccipital. The palatal concavity is deep, and the edges of the Bull. iv. No. 2—6

pterygoids are narrow. The supraoccipital process is long. Front nearly plane transversely. The mandibular ramus is of uniform depth from the coronoid forward, and the symphysis is subvertical. The inner alveolar edge extends almost to the symphysis.

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This species was found by C. H. Sternberg in the horizon in which the preceding species was obtained. It resembles it in several important features; but as the skull is unknown, it is not certain that it belongs to the genus Xerobates.

The general form is round, the carapace being shortened behind, where its outline is a segment of a circle. "The posterior marginal bones are vertical, and the edges are shortly recurved from one inguinal notch to the other. It resembles the X. orthopygius in the low buttresses which connect the base of the costal bones with the elevated inguinal margin of the hyposternal bone. The axillary margin of the hyosternal is not elevated. The posterior extremity of the plastron is openly notched. The anterior lip is unknown.

The carapace is flattened, but has a low tuberosity on the posterior part of the first vertebral scutum. In front of this, the superior surface descends to be again produced into the transverse flaring anterior liplike border. The surface of the costal bones is marked by grooves concentric with the border of the carapace, which are separated by obtuse intervals wider than themselves. The plastron is marked by grooves parallel with the longitudinal and transverse sutures.

The scuta are well marked. The pectoral is very narrow. The nuchal

is present and rather wide, and the vertebral scuta are quadrate in outline.

A number of specimens of this species was found, which vary somewhat in size.

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The largest of these is smaller than the two specimens of the X. orthopygius which I have examined.

PSEUDEMYS HILLII, sp. nov.

This water-tortoise, from the same formation as the Xerobates above described, is nearly allied to the existing species P. elegans Wied. It is represented by a single specimen, which embraces nearly the whole plastron, with numerous portions of carapace, cranium, and limbs.

The vertebral bones preserved are nearly as wide as long, are narrowed posteriorly, and possess a smooth surface. The costals are united with the marginals by gomphosis. Their surface is marked by rather distinct and remote grooves, which are parallel to the circumference of the carapace. The marginals are smooth, and their edges are acute, very little recurved, and medially entire, or nearly so. There is a notch at the point of junction of several pairs of the median bones, while there is a rather deep notch at the middle of the anal marginal, which is also not recurved, but straight. The dermal sutures are well marked. The osseous surface is delicately crimped below the costo-marginal suture, the grooves of which assume an obliquely posterior direction on the posterior half of each marginal bone.

The lateral border of the posterior lobe of the plastron is gently convex to the end of the anal dermal suture, where it is slightly concave, but not notched. The posterior extremity is slightly emarginate, and the postabdominals are broadly rounded. The mesosternal bone is not deeply received into the hyosternals. The plastron is flat, and the lateral buttresses are low. The superior surfaces of the borders are

but little thickened, and they pass gradually into the common surfaceof the plastron. The inferior surface exhibits a delicate grooving, which is parallel to the long axis of the animal; it is most distinct just behind the dermal cross-sutures. This species is about the size of the Pseudemys elegans. The typical specimen is adult.

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This species differs from the P. elegans in the absence of the median emarginations of the posterior marginal bones; in the absence of notch of the posterior lobe of the plastron at the end of the anal suture; and in the general absence of ridges on the costal bones. The median notch of the anal marginal bone is more pronounced in the existing species.

This tortoise was discovered by Russell S. Hill, to whom it is dedicated.

ART. XVII.-NOTES ON A COLLECTION OF FISHES FROM THE RIO GRANDE, AT BROWNSVILLE, TEXAS.

By DAVID S. JORDAN, M. D.

A small jar of fishes collected at Brownsville, Texas, has been lately discovered in overhauling the collections of the United States National Museum. The name of the collector and the date of the collection are lost, and most of the specimens are in poor condition from long neglect; still a study of them has added something to our meagre knowledge of the fish-fauna of the Rio Grande. With one or two exceptions, the species have all been described by Girard, often under several different names, in the Ichthyology of the United States and Mexican Boundary.

Family CENTRARCHIDÆ.

Genus LEPIOPOMUS Rafinesque.

1.-LEPIOPOMUS PALLIDUS (Mitchill) Gill & Jordan.

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1814-Labrus pallidus MITCHILL, Trans. Lit. and Phil. Soc. N. Y. 407.
Lepomis pallidus GILL & JORDAN (1877), Field and Forest, p.
Lepiopomus pallidus JORDAN (1877), Ann. N. Y. Lyc. Nat. Hist. 316.
Helioperca pallida JORDAN (1877), Ann. N. Y. Lyc. Nat. Hist. 355.
Lepiopomus pallidus JORDAN (1877), Bull. U. S. Nat. Mus. x, 43.

Lepiopomus pallidus JORDAN (1878), Man. Vert. ed. 2d, 241.

1818-Labrus appendix MITCHILL, Am. Monthly Mag. v. 2, 247. (Not Pomotis appendix DeKay et auct. L. auritus (L.) Raf.)

1831-Pomotis incisor Cuv. & VAL. Hist. Nat. des Poissons, vii, 466.

Pomotis incisor DEKAY (1842), N. Y. Fauna, Fishes, 33.

Pomotis incisor STORER (1846), Synopsis, 293.

Pomotis incisor AGASSIZ (1854), Am. Journ. Sci. Arts, 302.

Pomotis incisor GIRARD (1858), Pac. R. R. Survey, 24.

Pomotis incisor GÜNTHER (1859), Cat. Fishes, i, 259.

Ichthelis incisor HOLBROOK (1860), Ich. S. Car. 12.

Ichthelis incisor PUTNAM (1863), Bull. Mus. Comp. Zool. i, 6.

Lepomis incisor GILL (1864), Am. Journ. Sc. Arts, 93.

Lepomis incisor COPE (1865), Proc. Ac. Nat. Sc. Phil. 83.

Ichthelis incisor JORDAN (1876), Man. Vert. 235, 317.

Ichthelis incisor NELSON (1876), Bull. Ills. Mus. Nat. Hist. 37.

Ichthelis incisor JORDAN & COPELAND (1876), Check List, 138.

1831-Pomotis gibbosus CUVIER & VALENCIENNES (1831), Hist. Nat. des Poissons, vii, 467. Pomotis gibbosus STORER (1846), Synopsis Fishes N. A. 293.

1854-Pomotis speciosus BAIRD & GIRARD (1854), Proc. Ac. Nat. Sc. Phil. 24.

Pomotis speciosus GIRARD (1858), Pac. R. R. Surv. 23.

Pomotis speciosus GÜNTHER (1859), Cat. Fishes Brit. Mus. i, 263.

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