92 



August 25, 1856. 



Vice-President in the Chair. 



Mr. A. F. Beardslee was elected a Corresponding 



member. 



Donations to the Cabinet. 



From Mr. D. E. H >ugh —a specimen of Salmo ri- 

 vularis, Ayres, from Tetnaseal Creek. 



From Mr. Bloomer — a specimen of Limestone from 

 Suisun Valley. 



From Dr. Lanszwert — specimens of Eutainia dor- 

 salis, Pituophis catenifer and Jipodichthyi Jiavidus. 



From Dr. Eckel — two specimens uf Taenia solium 

 Donations to the Library. 



From Prof. J. D. Dana — '• Science and the Bible,'' 

 part 2d. 



From Mr. Schmolz — " Atomycwichts tablen zur 

 berechnung, von R. Weber." 



American Journal of Science, vol. 22, No. 64, was 

 received 



1856. 



October 20 



President in the Chair. 



Donations to the Cabinet. 



From Mr. Charles Earl — specimens of insects and 

 reptiles, from Chihuahua, Mexico. 



From Dr. Holrnaa — specimens ot Platichthys I'rom 

 the Rio Grande, near Panama 



From Dr. Veatch— specimens of Sulphur, Traver- 

 tine, Gelatinous Silex, aad Chalcedony, from the 

 Geysers ; also a specimen of Limouite from near 

 McDonald's Ranch, Berryessa Valley. 



From Mr. J. M. Alden — a specimen of Scomber 

 Diego, from the Santa Barbara Channel. 



From Col. Ransom — specimens of minerals from 

 the Great Basin, consisting of Obsidian, Pumice, 

 Travertine, and Copper ore ; also a package of bulj 

 bous roots called by the Indians of the Basin, " Ta- 

 boos," much used by them as food. 



From Dr. Stillman— specimensof Asteracanthion, 

 Cidaris. Hemiramphus and Chaetodon, trom Pana- 

 ma. 



Dr. W O. Ayres presented the following descrip- 

 tion of a new species of mackerel : 



Scomber Diego, Ayres. 



Body elongated, compressed, the thickness being 

 contaiued nearly twice in the length (The speci- 

 mens described were taken while the fish were not in 

 full condition, still the Scomber Diego is at all times 

 doubtless less rouaded than Scomber scomber or 

 Scomber vernalis.) Length of the head contained 

 tour times in the entire length ; depth of the body 

 equalling three fourths the length of th>- head. 



Eyes Urge, Tounded, separated from each other by 

 a space equal to their own diameter, which is con- 

 tained four times in the length of the head. Muzzle 

 pointed, jaws equal ; gape of the mouth moderate, a 

 line vertical to the tip of the maxillary crossing the 

 anterior part of the eye. Maxillary entirely and in- 

 termaxillary in large part received under a sheath 

 formed by the anterior suborbital. 



Teeth numerous, very fine and even, in both jaws, 



aud on the palatines, and a few on the vomer. — 

 Pharyngeals densely crowded. Anterior nostril the 

 smaller, circular. 



Scales numerous, rather small, soft, covering the 

 body, the bases of the second dorsal, aud caudal, and 

 the upper portion of the operculum aud preopercu- 

 lum ; remainder of the head naked, very smooth. 



Lateral line very nearly straight The first dor- 

 s il fin. which is thin and delicate, arising at about 

 one third or the distance from the tip of the tuout to 

 the extremity of the tail, is triangular in form, the 

 second ray equalling nearly the length of the fin or 

 halt the lenglh of the head. The fin when depressed 

 is entirely received in a groove. 



The distance between the two dorsals is equal to 

 the length of the first. The second is low, highest in 

 frout. tapering posteriorly, \l* greatest height being 

 less than half the height of the first dorsal, and its 

 length equal to twice its height. The space between 

 the second dorsal and the caudal is occupied by five 

 (inlets at about equal distances, the last having near- 

 ly twice the height of the others. 



The anal fin, arising a liitle further back than the 

 second dorsal, is entirely similar to that tin in form 

 and size. Between it and the caudal are five Unlets, 

 corresponding to those of the back. 



Pectoral ti is somewhat pointed, their length con- 

 tained a little more than twiceiu their height, which 

 latter is not quite equal to that uf the first dorsal. 



Ventrals a little posterior to the pectorals, which 

 they scarcely equal in height. 



Caudal fin very deeply lurked, the height of the 

 central rays being only one fourth ot that of the 

 longest, which latter equal one-seventh of the length 

 of the fish Depth of the body at the origin of the 

 caudal fin only one-half of the diameter of the eve 

 D 9 12 : A 112; P. 1!) ; V. 1 ."> ; C. 8 16 5 1 7. 

 Color, dark bluish green, with darker waving 

 lines above ; head greenish brown above; cheeks, 

 sides ami abdomen bright silvery. Tongue aud 

 membrane of the mouth and throat clouded, some- 

 times almost black. Fins agreeing in color with the 

 part of the body to wb ch they are attached. 



No specimens have yet been seen measuring more 

 than eleven inches in length, though it is stated that 

 they sometimes exceed that size by two or three 

 inches 



This fish is the only Mackerel known to inhabit 

 the coast of California. It occurs from Monterey to 

 San Dieuo, and probably extends its range much 

 further in both directions. We hear, in fact, of 

 Mackerel alonu our northern shores, but have seen 

 no specimens, and of course cannot decide upon the 

 species. None were contained in the collections 

 made in Washington and Oregon by Dr. Cooper and 

 Lieut. Trowbridge. 



S. Diego is allied very closely indeed to 8. verna- 

 lis, the mackerel of our New England const. It dif- 

 fers however in the form and proportions of the head, 

 in the contour of the body, in the eyes the lateral 

 line and the fins. 



We are not sufficiently acquainted with its histo- 

 ry to speak with confidence in regard to its migra- 

 tions. Most of the specimens received have been 

 taken in the Santa Barbara Channel, in the months 

 of August and September. It is quite abundant, 

 though never coining in such great numbers as the 

 Atlantic species. No attempts have yet been made 

 to render its capture a source of profit. 



Sax Farxcisco, Jan. 12,1857. 

 President in the Chair. 



