41. SONORA 865 
or greenish white, unmarked except on the tail, where the 
dorsal dark markings may be extended across the urosteges 
more or less obsoletely. 
Weeneth. to) anus oe 171 194 228 230 260 
Héenpthwiot tal 44 44 54 56 
Remarks.—In coloration this snake is more or Jess inter- 
mediate between S. episcopa and S. occipitalis. Its trans- 
verse black bars cause it to resemble the latter, while the 
tendency toward lateral lines recall the former species. The 
snout is very different from that of S. occipitalis but is like 
that of S. episcopa. S. semiannulata may be said to be prac- 
tically S. episcopa with black dorsal cross-bars. Its colora- 
tion reminds one in many ways of that of Rhinocheilus 
lecontei. 
Distridution—Originally described from Sonora, this 
little snake has since been taken in Texas, Kansas, Arizona, 
Utah, and Nevada. 
Arizona specimens have been recorded by Cope from 
Fort Whipple, Fort Verde, Prescott, and Fort Mohave, and 
I have seen others from the Huachuca Mountains, Cochise 
County, and Cave Creek, Maricopa County. 
In Utah, it has been taken at Rockville, Kane County, 
and near St. George, Washington County. 
In Nevada, one was captured at Pyramid Lake, Washoe 
County, and one at Rhyolite, Nye County. 
Flabits—Nothing is known concerning the habits of this 
little snake. The specimen from Pyramid Lake was found 
under a rock on a rise above the southwest shore of the Lake. 
