Mr. R. Schomburgk on the King of the Vultures. 255 



Easily distinguished from Planorbis corneus by the very 

 large size of the first whorl (which is wrinkled as well as 

 striated), by the number of whorls, and by the great size of 

 the aperture. It holds a place intermediate between Planorbis 

 corneus and some American allied species, such as Planorbis 

 trivolvis. I obtained this fine shell during a hurried and 

 dangerous %dsit to the eastern part of the plain of Metidja, 

 where I found it in a fountain along mth Physa contorta. 



43. Planorbis marginatum, Drap. (An Planorbis marmo- 

 ratus, Michaud, Test. Alg. ?) Ditches at Boufarik. 



Melanopsis. 



44. Melanopsis buccinoidea, Ferr. On stones in the stream 

 at Boufarik. 



PiSIDIUM. 



45. Pisidium Lumstenianum, nov. sp. PI. XII. fig. 4. 



P. testa ovata, oblique trigona, tumida, infequilatera, transversim 



striata, natibus prominentibus, roseo- cornels. 

 Br. 3" ; length Jq inch. 

 Fountains in the Metidja. 



XXIX. — On the Habits of the King of the Vultures (Sarcor- 

 rhamphus papa). By Robert H. Schomburgk, CM. 

 B.G.S., Lyceum of Natural History in New York, Hono- 

 rary Member of the Bristol Institution, &c. 



The most beautiful of the deformed family of the vultures 

 is doubtless the Sarcorrhamphus papa, upon which in conse- 

 quence the royal title has been bestowed. It is an inhabitant 

 of South America, and appears to be abundant in Guiana, 

 where it has come under my notice from the coast regions to 

 the equator. I might compare it in size, without going to 

 actual admeasurement, to a full-grown turkey cock. Its bill 

 is two inches in length, and its depth amounts almost to the 

 same measure, being 1*9 inch. The upper mandible is covered 

 by the cere, and straight in the beginning, but bent at its 

 point to a hook ; the lower mandible is straight, rounded, and 

 scarcely inflected. The nostrils, which are within the cere, 

 are lateral and situated close to the ridge of the upper man- 

 dibles ; they open obliquely towards the point of the beak : 



