ones (about 24 on the body-whorl); two very distinct revolving lines on the last volution, the upper one placed at about the middle, the lower one subcarinating it (only the upper of these two lines is seen on the remaining whorls, appearing there as a central line); base striated by revolving lines, and radially by the continuations of the transverse lines; apperture elliptical, somewhat produced distally.

Volutions seven or eight, the earlier three or four convex, the remainder flattened; body-whorl subangulate; suture impressed; aperture less than one-half the length of shell, the canal sharply twisted; columella with a pseudo-fold following the curve of the canal. The whorls in the single specimen before me are destitute of ornamentation, but some traces of the former existence of revolving lines are apparent. Length, inch. (No. 8917.)

Atascosa County, Texas.

Named after Mr. G. W. Marnoch, through whom this and other species of older Tertiary Texas fossils have been obtained.

TEREBRA, Lam.

TEREBRA PLICIFERA, n. sp.

Plate, fig. 8.

Turreted; whorls? in number, flattened, rapidly decreasing in size from the base upwards, and ornamented by numerous broad and prominently defined plicæ, having a sigmoidal flexure; an impressed line on the upper portion of each volution produces a subsutural ring or band, over which the plica and corresponding sulci are continued, and which occasionally tends to become double from the presence of a second impressed line. Body-whorl with two elevated revolving lines on its basal angulation; base radiately and longitudinally striated; aperture? (broken in all specimens).

Length (No. 8919.)

Atascosa County, Texas.

CRASSATELLA, Lam.

CRASSATELLA DECLIVIS, n. sp.

Plate, fig. 9.

Very inequilateral, somewhat inflated anteriorly, the posterior dorsal margin descending very obliquely to the extremity, which is subcunei

form; anterior margin descending rather abruptly, obtusely rounded; basal margin somewhat sinuous posteriorly. Surface deeply sulcated for the greater portion, the sulci mainly disappearing on the umbonial slope, where they give place to finely crowded striæ; apex acute; muscular impressions impressed; margin minutely crenulated.

Length, 13 inches. (No. 2490.)

Aquia Creek, Virginia.

APRIL 25, 1880.

DESCRIPTION OF A NEW AGONOID FISH (BRACHYOPSIS XYOSTERNUS), FROM MONTEREY BAY, CALIFORNIA.

By DAVID S. JORDAN and CHARLES H. GILBERT.

Brachyopsis xyosternus sp. nov.

Form of head and body as in Brachyopsis verrucosus Lockington. Body elongate, depressed, broadest at the shoulders, thence tapering rapidly to the snout, and gradually and evenly to the tail. Snout broad, obtuse, depressed, its sides parallel. Mouth terminal, very oblique, the lower jaw much the longer, its tip projecting upward above the upper profile of the snout. Mandible very broad, its greatest depth one-third its length, maxillary reaching to half way between front of orbit and pupil. A long barbel three-fourths the diameter of the orbit at its end. Premaxillaries anteriorly above the level of the pupil. Jaws with bands of villiform teeth. Vomer and palatines with slight asperities. Nasal spines present. No spines on top of cranium. Interorbital space broad, concave, from the elevation of the supraocular ridges. Preorbital with two spines. A sharp spine on the suborbital at lower posterior margin of eye. Preopercle with four processes, the upper one a sharp spine. Opercle striate, without spine. Top of head and the upper parts of the body without the small prickles which are found in B. verrucosus. Occipital pit obsolete.

No isthmus, the gill membrane united across the breast. No slit be hind the last gill.

Body with the usual eight series of long keeled plates. Each keel terminating in a strong spine hooked backward, striæ radiating in every direction from the spine.

Dorsal series of plates 32, 6 before the spinous dorsal, 6 along its base, 4 between the two dorsals, 5 along the base of the soft dorsal, and 11 behind it. The two dorsal series uniting immediately behind the soft dorsal, the resultant single series round, with radiating striæ, the keeand spine obsolete. The two abdominal series similarly unite close behind the anal fin.

The plates in the upper lateral series diminish in size forward, becoming very small anteriorly. The lower lateral series becomes broader forwards as the other series decreases. It terminates abruptly opposite

the origin of the second dorsal. In the lower lateral series are 29 plates, in the abdominal series 30, 10 before the anal, 8 along its base, and 11 behind it.

Breast without distinct plates, but entirely covered with minute tubercles) each of which has a central spine. A series of five plates in front of the base of the pectorals, four of them armed with hooked spines.

Fin rays: D. VI-6; A. 8; V. I, 2.

Lowest rays of pectorals not so short as in B. verrucosus, the lowermost two-thirds the length of the longest (in B. verrucosus two-sevenths). Pectorals barely reaching front of anal.

Ventrals much shorter than in B. verrucosus, the tips reaching slightly more than half the distance to the anal fin (beyond front of anal in B. verrucosus). Inner ray of ventrals very little longer than the outer, the connecting membrane narrow (very broad in verrucosus). Vent but little behind ventrals.

Coloration.-Upper parts dusky; mandible, cheek, and subopercle silvery. Belly pale, with reddish tint. Lower half of pectoral reddish at base, the rest of the fin thickly dusted with black points. Ventrals reddish. Dorsal membrane immaculate, the rays punctulate with black. Caudal blackish. Anal reddish anteriorly, dusky behind.

This species is related to Brachyopsis verrucosus, lately described by Mr. Lockington, differing, however, in several important respects, especially (a) in the presence of small prickles on the breast instead of the large wart-like plates characteristic of verrucosus, (b) in the short ventral fins, (c) the absence of small prickles on the plates of the body, (d, the smaller number of plates, (e) the shorter vertical fins, (ƒ) the long maxillary barbel, and (g) the deep mandible.

Brachyopsis verrucosus is comparatively common in the open water between Point Reyes and the Farallones, and is frequently brought in in the trawl-nets. Brachyopsis xyosternus is thus far known only from a specimen found on the beach at Santa Cruz by Dr. C. L. Anderson, and presented by him to the United States National Museum.

The genus to which these two species belong is well separated from Agonus by the absence of an isthmus, as well as by the entirely different form of the mouth and anterior portion of the head. Whether they are congeneric with the type of Brachyopsis Gill (Agonus rostratus Tilesius, from Kamtschatka) is yet to be proven.