NATURAL SCIENCES OF PHILADELPHIA. 297 



Rhinosimus (D. and B.) placed by Giinther among the Calamarinse, differs 

 only in the keeled, recurved rostral, and Rbinostoma Fitz., the only other 

 genus with grooved maxillaries, has the recurved rostral, with divided urosteges. 

 The form and glossy smoothness of the Olisthenes euphaeus admirably 

 adapt it for making its way among pieces of bark, decayed logs, and other 

 debris of the forest. Its native country is unknown to us, but as it was ob- 

 tained in ajar containing a specimen of the species below mentioned, it proba- 

 bly came from South America. 



CORONELLINJE. 

 Liophis vittatus. Coluber vittatus Hallowell, Proceed. Acad. Nat. Sci., 

 Vol. ii. p. 242. The serpent described as above, from specimens brought by 

 Mr. Ashmead from Venezuela, is a true Liophis, resembling the L. reginae, 

 taeniurus, and conirostris, but without the transverse markings of 

 the first and second, and the peculiar plating of the last. There are numerous 

 specimens in the Acad. Mus. It does not appear to be known to European 

 herpetologists. 



Descriptions of two new species of Carboniferous Fossils, brought from Fort 

 Belknap, Texas, by Dr. Moore. 



BY W. M. GABB. 



Myalina deltoidea. Shell triangular, flattened, beaks narrow, tapering 

 and curved anteriorly ; cardinal margin slightly curved and nearly as long as 

 the anterior edge ; anterior edge gently sinuous ; posterior edge nearly straight ; 

 basal edge rounded ; umbones subangular ; umbonal ridge running parallel 

 with the anterior border losing itself near the basal edge ; anterior umbonal 

 slope perpendicular to the plane of the valve ; posterior umbonal slope gentle, 

 and extends to the posterior edge ; inside, the cardinal third of the shell shows 

 an alation which is invisible exteriorly ; surface marked with indistinct con- 

 centric lamellae. 



This shell was found near Fort Belknap, either in the coal or in the stratum 

 of dark blue shale overlying the coal. The specimens, consisting of a left 

 valve, nearly perfect, and several fragments of the beaks showing the hinge 

 well preserved, are replaced by pyrites. 



Posidonia Moorei. Shell subquadrangular, slightly gibbous, cardinal 

 edge straight ; beaks small, near the anterior edge, and slightly projecting be- 

 yond the cardinal line ; umbones prominent, anterior edge rounded ; posterior 

 edge straight above, rounded below to meet the basal margin, which is regulaly 

 curved ; surface marked by about twenty prominent round concentric ribs. 



Locality and Position. From a buff colored limestone above the coal, near 

 Fort Belknap. 



Descriptions of supposed new species of Birds from Cape St. Lucas, Lower 



California. 



BY JOHN XANTUS. 



A sojourn of several months at Cape St. Lucas, Lower California, besides 

 furnishing many species of birds not found by me at Fort Tejon,* has brought 

 to light several species, which, as far as I have now the means of judging, 

 seem to be entirely new. I subjoin descriptions of those which appear to be 

 most decidedly undescribed birds, although it is very probable that a careful 



* See Proceedings Acad. Nat. Sciences, August, 1859, for a list of birds collected by me 

 at Fort Tejon, California. 



1859.] 



