Rings very irregular and imperfect. Some fine, spongy appearance connected with the secondary bronchi in anterior and middle part of lungs, but posteriorly, the structure, instead of being cellular, seems to consist of a very coarse, loose net-work made up of fine, white, tendinous cords. No muscular fibres detected.

There was a great quantity of Fat in the male tortoise, filling up the space on each side in the upper shell just above the junction with the lower. In the female this had in a great measure been absorbed, and was very much altered in appearance.

Organs of Locomotion in the male tortoise. The bone, compared by Cuvier to the os quadratum, terminates in a transverse, articulating surface in the form of a groove which receives a corresponding ridge in the lower jaw; in the female, instead of a groove, the upper surface has an arched, concave form. Zygomatic arch quite narrow. Temporal fossa very large, giving origin to a muscle of proportionate size. Articulating surface of occiput with atlas very prominent, much more so than in the green turtle, allowing great freedom of motion. Eight cervical vertebræ; most of them have a ball and socket joint, the posterior extremity being convex; the third is convex at each extremity; the longest are situated about midway and measure four inches; towards the union with the back shell they become much shorter but in proportion thicker, and the processes very prominent; the atlas is scarcely an inch in length and neither are the spinous processes united together nor are the sides to the body of the bone. There seems to be no good reason, however, why this bone should be excluded from the list of vertebræ as Cuvier has done, though it is so little developed (Anat. Comp. i, 172); the dentatus, also, is quite small, and

the odontoid process is a distinct piece. The muscles are numerous, but very distinct, as, indeed, they were in every part of the body; some arising from the upper shell and some from one or more vertebræ to be inserted into those above; one pair arises from the dorsal vertebræ, nearly or quite as far back as the sacrum, is inserted into three of the cervical vertebræ and at last reaches the base of the skull. The muscles of deglutition or of respiration, on the front of the neck, which raise and depress the large hyoid bone, are also very interesting, and especially a pair which passes transversely nearly around the upper half of the neck, arising from the articulating processes and reaching as high as the temporal bone. That peculiar bone, which has received so many names and none more appropriate than that of lunula, which it owes to its form, was about fourteen inches long, formed of one continuous piece and united at each extremity to the upper and the under shells by a short and very strong ligament. The scapula is firmly attached to it, five inches from the lower extremity, and is somewhat triangular, extending backwards four and a half inches. The humerus is nine and a half inches long and four and a half inches in circumference midway; head of the bone round and near it are two tuberosities, one of which is of immense size; lower articulating surface has a convex, oblong form. Radius and ulna from five and a half to six inches long; no olecranon; lower end of ulna larger than that of radius. There are eight carpal bones, one of which seems formed by the union of two; besides these, there are three bones to each toe, all of which may be considered as phalangeal or one of them may be regarded as a metacarpal bone; besides a row of five metacarpal bones, Carus gives three phalangeal to the three middle toes and two to each of the two others

(Comp. Anat. i, 150). The muscles which move the shoulder are of immense size; one, which is probably the largest in the body and entirely fleshy, arises from almost the whole anterior half of the under shell and is inserted into the small trochanter at the head of the humerus; the others take their origin principally from the lunula and scapula, except a few from the upper shell and go to be inserted in and about the great trochanter of the humerus. The long flexor and extensor of the forearm also arise from the scapula, except for one head of the last. Below these the different parts of the upper extremity have their flexors and extensors, pronators and supinators very much like the higher classes. Of the vertebræ, besides the cervical, there are eight dorsal, four sacral and twenty-one caudal. The sacrum unites firmly with the pelvis, but moves freely on the last dorsal vertebra, as do the ilia also by a broad surface on the transverse processes; all of these articulations have a synovial membrane, as have also, those of the caudal vertebræ. The symphysis pubis, as it is usually called, is quite broad and in this case formed about equally by the ossa pubis and the ischia, the limits being quite distinct as the three coxal bones are not united by ossification; anteriorly it is flat and pointed, posteriorly broad and thick; from the anterior edge of the pubes a very prominent spine arises, two and a half inches long, about as large as the middle finger and directed outwards to receive a muscle arising from the under shell. Obturator foramen an inch and a half in diameter and nearly circular. The femur is seven and three fourths inches long and altogether considerably smaller than the humerus; has a single trochanter at upper extremity of moderate size, the lower having a convex oblong form. Tibia and fibula five and a fourth inches long. There are seven

tarsal bones; one only articulates with the leg and this is very much larger than any of the rest-towards the outer extremity, however, and on one side is a line as if there had formerly been a small separate bone; to one of the tarsal bones which is situated on the outer edge, and projects quite beyond the rest, there is attached a very small bone, which appears to be the rudiment of another toe. Each of the four toes has three bones, to which the same remarks will apply that were made in the case of the anterior extremity. The muscles of the posterior extremities generally, were smaller than those of the anterior, and in proportion to the size of the bones; one, which was attached quite round the posterior margin of both shells, was admirably calculated to expel the air from the lungs, by forcing the organs in upon them.

ART. XXIII.-DESCRIPTION OF A NEW SPECIES OF THE GENUS GASTEROSTEUS. BY D. HUMPHREYS STORER, M. D. Read January 17th, 1837.

Or the fifteen species belonging to the genus GASTEROSTEUS of Linnæus, described in Cuvier's Histoire Naturelle des Poissons, four belong to the United States. Two of these had been previously described and figured by Mitchell, in his Fishes of New York. Of these, one, the quadracus, belongs to our Cabinet. In presenting a new species, for which I am indebted to Mr. John W. Randall, I would offer the accompanying description.

Storer's Description of a new Marginella. 465

GASTEROSTEUS MAINENSIS.

Color yellowish, with transverse black bands. Seven spines anterior to the dorsal fin.

The length of this fish is about two inches. Its general color is on the sides yellowish, beneath silvery. Several black bands, varying in their width, commencing at the operculum and terminating at the tail, cross it transversely from the dorsal fin to the abdomen. Seven spines exist upon the back, that next the dorsal fin is larger than the others. Eyes large. Nostrils bordering upon the upper angle of the eye. Mouth moderate in size. Teeth prominent. One broad, oblong, serrated plate, almost hidden by the pectoral fin when expanded, is observed upon the side. Ventral fin serrated upon its upper edge. The fin rays are,

D 7-10. P 10. V 1. A 1-8. C 8.

Taken from fresh water in Kennebeck County, State of Maine.

ART. XXIV.-DESCRIPTION OF A NEW SPECIES OF

MARGINELLA.

Feb. 1st, 1837.

BY D. HUMPHREYS STORER, M. D. Read

MARGINELLA CARNEA.

Plate X. Fig. 2.

M. Testâ ovato-oblongâ, rubrâ; vittâ transversâ albidâ ; spirâ brevi conicâ, obtusâ; aperturâ angustatâ ; labro crasso, albo; columellâ quadriplicatâ.

SHELL oblong, of a beautiful flesh color; below the middle of the lowest whirl crossed transversely by a