NATURAL SCIENCES OF PHILADELPHIA. 3 



Catalogue of Birds collected on the rivers Camma and Ogobai, Wes- 

 tern Africa, by Mr. P. B. Duchaillu, in 1858, with notes and descrip- 

 tions of new species, by John Cassin. 



Descriptions of two new species of tortoises, by John Le Conte. 



Geological Explorations in Kansas Territory, by F. B. Meek and F. 

 V. Hayden, M. D., 



And were referred to Committees. 



Dr. Morris described a new species of Pomotis very common in the vicinity 

 of Philadelphia, and characterised by a short auricular appendage and rounded 

 caudal fin. The numbers of the rays are as follows : 



D. 9-10. A. 3-9. P. 9. C. 16. V. 1-5. 



The dorsal, anal and caudal fins are covered with spots of a lighter color 

 than the fins themselves. The body of the fish is traversed by seven or eight 

 blackish bands, the first passing through the eye, the second near the margin 

 of the opercle, the third behind the pectoral, the fourth and fifth opposite the 

 dorsal, the sixth, seventh and eighth from opposite the end of the dorsal to the 

 root of the caudal. An opaline bluish spot is found on the opercular appen- 

 dage, the general color of which is black. This species approaches the P. 

 catesbei of Cuv. and Val. but is believed to be distinct. Dr. M. proposed for 

 it the name of Pomotis guttatus. 



Dr. Leidy called the attention of the members to some remains of cartila- 

 ginous fishes, discovered by Dr. F. V. Hayden and F. B. Meek, during the last 

 summer, in the carboniferous formations of Kansas. One of these is a muti- 

 lated dorsal spine included in a fragment of rock, from ihe upper carbonife- 

 rous formation of Leavenworth City. The spine may perhaps belong to one 

 of the same fishes, to which the other specimens appertain, but there was no 

 means at present to determine this fact. It was characterised as follows : 



Xystracanthus arcuatus Leidy. Spine much curved ; its posterior border 

 formiDg the segment of a circle whose diameter would be about 2 inches. 

 Length along the convex border, when perfect, about 2| inches. Lower ex- 

 tremity 3| lines wide. Section ovoid with the broader part posterior. Sides 

 of the spine finely ridged longitudinally, and furnished anteriorly with small, 

 oblique, hemi-elliptical tubercles ; posteriorly provided, on the two sides together, 

 with six rows of odontoid tubercles, of which those of the first row on each 

 side are minute, and of the last row are the largest. Osseous structure of the 

 specimen brown ; odontoid tubercles invested with smooth, shining gray, ename- 

 loid substance, demi-conoidal, those of the posterior pair of rows sometimes 

 coalescing across the back border of the spine and assuming a crescentoid 

 form. 



The second specimen was the fragment of a tooth, of a species of Cla- 

 dodus, obtained from the Manhattan upper coal measures. It was characterised 

 as follows : 



Cladodus occidentalis Leidy. Enameled crown, when perfect, about an 

 inch in length, demi-conical ; the outer convex side provided with narrow ob- 

 lique folds. Lateral denticles two, the outer one the larger. Base of the tooth 

 reniform, with a breadth of about an inch, and the short diameter about 5 

 lines ; lateral extremities provided with a pair of large ovoid tubercles, one 

 above the inner margin, the other below the outer margin. 



The third specimen is a tooth, apparently of Petalodus alleghaniensis,* 

 from the upper carboniferous rocks, near Fort Riley. It differs from the tooth, 

 upon which the species was originally founded, in no important point, except 

 that it is larger. The breadth of the crown is about twenty lines ; its height 

 on the convex side 10 lines, on the concave side 1 inch. 



* Journ. Acad. Nat. Sci. iii, 161. 



1859.] 



