t 
- cS 
‘Oct., 1907. Meteorite Stupies I] — Farrincton Io5 
‘as shown in several of the plates. The crackle has a mesh-like 
: pattern With meshes in the form of polygons, squares and triangles 
from 4% to % inch on a side. The appearance is entirely similar 
to that presented by crackled earthen ware and is doubtless produced 
by shrinking of the crust in cooling, or expansion of the interior of the 
meteorite subsequent to the formation of the crust. Another interest- 
ing feature seen on the crust of several individuals is that of glazed 
spots of occasional occurrence. The spots are usually of a greenish 
color, oval to circular in area, and vary from % to % inch in diameter. 
They doubtless mark the location of chondri of fusible composition. 
Under the microscope the crust shows in cross section a thickness 
of about .5 of a millimeter. The three zones of Tschermak are plainly 
marked, with widths averaging as follows: Fusion zone .o25 mm., 
absorption zone .t mm., impregnation zone .4 mm. ‘These zones ex- 
hibit the usual characters, the fusion zone being black, opaque and 
glassy, the absorption zone transparent, and the impregnation zone 
showing a large proportion of black, opaque matter. The relative 
widths above given remain fairly constant, although in places the ab- 
sorption and fusion zones are of about equal width, and again the 
absorption zone may disappear altogether. The fusion zone is at 
times also blebby and rough in outline. The interior of the meteorite — 
is megascopically ash-gray in color, in some individuals flecked with 
rusty spots. The substance is only fairly coherent, and will not polish. 
PONCA CREEK. 
The writer proposes the name of Ponca Creek for the meteorite usu- 
ally known as Dakota. The reasons for the change are as follows: 
The original account by Jackson* states that the fragment which he 
described was given him by the U.S. Indian agent for the Ponca tribe 
of Indians, and further that the mass was found on the surface of the 
ground “in the Dakota Indian territory, ninety miles from any road or 
dwelling.” In the repetition of this statement by foreign authorities 
a comma came to be inserted after Dakota, so that the locality was 
known as Dakota, Indian Territory. .There is no such locality, how- 
ever, and Indian Territory is several. hundred miles removed from the 
place where the meteorite was found. Moreover, the original territory 
of Dakota, within which the meteorite may have been found, is now 
subdivided into North and South Dakota and neither namewould desig- 
nate the locality in a sufficiently limited way. The reservation of the 
Ponca Indians, who were a tribe of the Dakotas and from whose agent 
*Am. Jour. Sci. (2) 36, pp. 259-261. 
