but some distance from the latter, a colony of nests but very recently abandoned. Over the locality and screaming about our heads were a few of this species, and no others. The nests, some fifteen or twenty in number, were composed of little bunches of grass in saucer-shape, and contained bits of broken shells and fresh excrement, with abundance of the latter about the nests. Some three hundred or more feet distant were the Forster's Terns mourning over their losses. As we left the nests of the Marsh Tern, the parent birds followed us for a short distance, and then flew away from the island. The island was small, and situated far out in the shallow water. The bird shot for identification was a male. Fortunately, we found an unfertilized egg. In shape it closely resembles that of S. forsteri, but it is more roundly pointed. In color, the drab, instead of being yellowish, has a slight greenish tinge. The markings are also similar to those of Forster's Tern in form and color, but are more thickly placed near the larger end. It measures 1.78 by 1.34 of an inch. 2-9-14.25 x 36.00 x 11.25 x 3.90. 442--15.25 x 37.50 x 11.90 x 4.60. Winter plumage, Feb. 28, Galveston. STERNA CASPIA, Pall.-Caspian Tern. I met this fine bird in limited numbers all the way from Galveston to Padre Island on the coast. I saw more about Galveston than at any other point. Bill red, dusky-tipped. Feet black. Iris hazel. 1--21.60 x 53.00 x 16.50. Feb. 28, Galveston. Feb. 28, Galveston. 4-9-22.50 x 55.25 x 17.00 x 6.50. Feb. 28, Galveston. STERNA CANTIACA, Gm.-Sandwich Tern. This long-billed little fellow was seen in abundance about Corpus Christi Pass. No specimens were secured, but I have received a skin from there since my return. They breed in that vicinity. STERNA FORSTERI, Nutt.-Forster's Tern. I found this species quite numerous at Galveston, March 1st. On May 16th, I found it breeding in the salt-marshes on the Rio Grande. I became familiar with this Tern in the spring of 1876 in Western Minnesota, and to find it here again was like meeting an old friend. On the same low and nearly submerged island where we found the eggs of Stilt, Himantopus nigricollis, and some hundred yards or more distant, was a group of these Terns upon the ground near their eggs. When we approached them, they commenced screaming and flying about in great distress. They had only fairly begun to lay, as no set was complete. One or two eggs were all that any nest contained, and some were not occupied. The nests were situated farther away from the water than the Stilt's, but still where the mud was wet, and consisted simply of a patting-down of grasses and soil into a shallow saucer-shaped depression. About twenty eggs were secured between Dr. Merrill and myself. Several Bull. iv. No. 1—5 birds were shot; but as I had more valuable skins to prepare, I could not preserve them. Eggs with ground-color drab, with a more or less yellowish tinge, and pretty evenly covered with spots and dashes of different shades of brown; average size 1.86 by 1.37. 4--14.75 x 30.00 x 9.75 x 5.00. Winter plumage, Feb. 28, Galveston. STERNA SUPERCILIARIS ANTILLARUM, (Less.) Coues.-Least Tern. I did not notice this smallest of the Terns until I reached the Rio Grande. Along the bed of the river between Brownsville and Hidalgo it was seen frequently. Only one specimen secured. Its mate fell in the river and was lost, as were several that had been shot before. It undoubtedly breeds on the border, but I did not meet with its nest. On my return to the coast I again saw it. 416-3-9.75 x 19.75 x 9.60 x 3.60. May 11, Hidalgo. RHYNCHOPS NIGRA, L.-Black Skimmer. I saw a few of these curious birds at Corpus Christi and Point Isabel. The largest group I saw was of four. The rest were generally in pairs. They were flying near the shores of the bays, and did not appear shy. PODICIPIDE. PODICEPS DOMINICUS, (L.).—San Domingo Grebe. I saw From their extremely small size I am sure I saw several of these cunning birds, but I must own to my not being able to shoot them. them in the lagoons and marshes, but they are by no means abundant. ART. II.-DESCRIPITONS OF FISHES FROM THE CRETACEOUS AND TERTIARY DEPOSITS WEST OF THE MISSISSIPPI RIVER. BY E. D. COPE. TRIÆNASPIS VIRGULATUS, Cope, gen. et sp. nov. Character genericus.-Shape anguilliform; vertebræ elongate, contracted medially, furnished with wide and short diapophyses over the abdominal region. Cranium elongate, not beaked; jaws furnished with acute teeth of moderate size (but small number in the typical specimen). Dorsal fin short, median in position, its radii cartilaginous. Ventral fins entirely behind dorsal. Caudal and anal fins unknown, the latter probably wanting. The dorsal and ventral surfaces each protected by tripodal shields. Shields of other forms on the sides. This, with the genus following, introduces for the first time into the North American extinct fauna the family of the Dercetiform fishes. The relationship of the family has been discussed by various authors, especially by Pictet and Von der Marck. The former regards them as Teleostei; the latter as "Ganoids". As I do not adopt the division signified by the last name, I find Professor Pictet's view nearer to the point. The specimens indicate further that the Dercetida belong to the Actinopteri, and probably to the order Hemibranchii. The only alternative is the order Isospondyli, and the characters which separate the two are not clearly shown in the specimens. Distinct bones below the pectoral fins may be interclavicles, which belong to the Hemibranchii. As compared with the other genera of this family, Trianaspis differs in the very short dorsal fin and posterior position of the ventrals, with the probable absence of the anal. The scuta differ in form from those of some genera. Character specificus.-The head is relatively large and the body slender. The fins are all small. The rami of the mandible do not present a long symphysis. The opercula are subround, and the bases of the pectoral fins are quite posterior to them. The dorsal and ventral scuta are triradiate, the median branch of the three being directed anteriorly. A series of smaller triradiate scales extends along the superior lateral region just below the dorsal row, and there is a similar one above the abdominal row on each side. Between these and the vertebral axis there are numerous narrow, band-like scuta, directed backward and toward the vertebræ. Radii: D. 9 or 10; P. 12 or 13; ventrals disturbed. Vertebræ: to first ray of dorsal fin, 27-28; from dorsal first ray to opposite base of ventral fin, 10. The dorsal and ventral scuta correspond in number to the vertebræ. Measurements. This fish was discovered by Dr. F. V. Hayden, Geologist-in-Charge of the United States Geological Survey of the Territories in the Niobrara Cretaceous horizon of Dakota. LEPTOTRACHELUS LONGIPINNIS, sp. nov. This species agrees with the type-species of Leptotrachelus of Von der Marck in the position of the ventral fins beneath the dorsal, in the great elongation of the anterior vertebræ, and in the lanceolate form of the head. It differs from that species (L. armatus v. d. Marck) in its more elongate dorsal fin, in which it approximates the genus Dercetis. Two incomplete specimens represent this species, neither of which possesses the caudal nor exhibits an anal fin. In one of them, the cranium is preserved in a somewhat dislocated condition at the extremity of its very long peduncle. The vertebræ of this region, which might be called a neck, are several times as long as those of the dorsal series. The femoral bones are slender, and commence below the anterior part of the dorsal fin. In one specimen, the ventral fin originates below the twelfth dorsal ray; in the other, below the fifth. As the latter is the least distorted, I suspect the fin to occupy its normal position. The dorsal radii are slender, and the middle and anterior longer than the posterior; they number twenty-seven in one specimen, and nineteen in the other, where the posterior portion is broken away. The ventral rays are hair-like, and do not extend to the line of the distal end of the dorsal. The pectoral fins are well developed, and occupy their usual position. The cranium is much dislocated, but the snout is acute and attenuated. The dermal scuta consist of median, dorsal, and ventral rows of tripodal form. There are some slender, longitudinal, hair-like bodies on the sides, which cross the ribs. The vertebræ present the characteristic elongate centra. The diapophyses are longer on the postventral than on the preventral region. Each scutum is as long as a vertebra. Measurements. Discovered by Dr. F. V. Hayden in the Niobrara Cretaceous of Dakota. This fish is particularly welcome, as displaying generic identity with a species of the Westphalian Chalk, and with a third, from the Slates of Mount Lebanon. It thus indicates a closer relation between these fannæ than could be predicated on the discovery of the family to which it belongs. The horizon of Mount Lebanon has been regarded as Eocene, but Heckel and Von der Marck place it in the Upper Cretaceous. To the conclusion of these palæontologists, the discovery of this and other species described in this paper lends support. ICHTHYOTRINGA TENUIROSTRIS, gen. et sp. nov. Character genericus.-Head attenuated and produced into a beak; jaws with weak teeth, of equal lengths. Dorsal fin small, composed of soft rays. Body covered with small, round scales. Vertebræ sub elongate. The specimens representing this genus are so far imperfect that the caudal and anal fins remain unknown. But they show clearly that it differs from the genera which appear to be related, namely, Dercetis and Rhinellus, in the absence of dermal scuta and in the short dorsal fin. But one species has come under my observation. Character specificus.-The dorsal fin is about half as far behind the cranium as the length of the latter. It is supported by well developed interneural spines; but these elements do not exist in front of it. Muzzle very slender, the mouth apparently opening to behind the orbit. The scales closely imbricate, in about twenty longitudinal series, above the vertebral line of the side. Dorsal radii, II. (rudimental), 12. The superior supplementary ribs are numerous. Measurements. Length to opercular border Length to base of first dorsal ray.. Length of base of dorsal fin Elevation of dorsal fin....... Depth to vertebral column between dorsal fin and head Five vertebræ From Cretaceous No. 3 of Dakota (Dr. F. V. Hayden). SPANIODON SIMUS, sp. nov. M. 0.043 0.061 0.006 0.010 0.005 0.006 Another genus of the Lebanon is represented in the collections from Dakota by a rather abundant species. The elongate anterior teeth of the dentary bone and the edentulous maxillary are exhibited by the |