259 



which passes under it, and they form a patch on the sides of the 

 neck extending round to the nape. Chin, throat, and breast 

 white ; flanks and abdomen h'ght yellowish brown, darkest near 

 vent. On the rump are some white and dark brown or black 

 spots intermixed with the brown of the rest of the back. Under tail- 

 coverts, the outermost, and oiAter webs of next three tail-feathers, 

 and outer edges of first and second primaries, barred with white 

 or yellowish white, and dark brown or black. There are many 

 black bars running across upper side of wings and upper tail- 

 coverts. The four middle tail-feathers are brown, with many 

 black spots. The upper mandible is dark horn color; the under 

 mandible is the same at its tip, but is almost white on the under 

 side and at base. The fourth and fifth primaries are longest and 

 the first is shortest. 



The specimen from which the description was taken was the 

 only one observed, and was procured near Yalahao, in Yucatan, 

 April 6th, 1842. 



Dr. Cabot also announced the donation from Maj. Town- 

 send, of two specimens of Birds from Arkansas, namely, 

 Icterus xanthocephalus and Recurvirostra Americana. 



Dr. Gould exhibited specimens of Planorbis muUivolvis, 

 Case, brought by Mr. C. J. Foster from the Lake Superior 

 region, recently described by Mr. Case in Silliman's Jour- 

 nal. It is a very decidedly-marked species. Dr. Gould 

 thought that some other specimens accompanying them, 

 allied to T. hicarinatus, were also new. 



Mr. Peabody presented a bottle of small Fishes, from 

 Lake Superior, collected at the suggestion of Prof. Agassiz. 

 He also exhibited specimens of Fluor Spar, of various forms 

 and colors, from the mine of C. A. Stickney, Esq. Shaw- 

 neetown, 111. He also pointed out crystals of Cadmium 

 Blende, of which he gave the following results of analysis : 

 Silica 4.800; iron 6L000; cadmium 3.100; sulphur 31.000. 



Dr. C. T. Jackson exhibited specimens of Copper from 

 the Bruce mine, north side of Lake Superior ; Copper Py- 

 rites and Grey Sulphuret mixed with Quartz rock, of a rich- 

 ness estimated at 15 per cent. He also exhibited a lump of 



