526 The American Naturalist. [June, 
this surface that in only one or two places i is it possible for even 
a mule to find his way across the lava. The stage road is 
deflected by it for a distance of several miles, then crosses it at 
the narrowest part, running for the entire distance over bed-rock, 
which rings with a- metallic ring under the hoofs of the horses 
and the wheels of the wagon. On either side of the road is an 
impassable desert of boulders, slaggy and black, and ranging in 
size from mere splinters to large blocks many tons-in weight. 
Frequently it is possible to see where the consolidated crust of 
the flow burst asunder and a small side stream issued forth, cool- 
ing and cracking into slaggy, vesicular splinters and blocks. At 
other places the lava surface has broken into innumerable pieces, 
as if under the influence of some irregularity in the underlying 
topography. Not uncommonly the surface has been thrown into 
rounded waves, and cooled with the ropey surface so characteristic 
of some lava flows. The action of the weather has made no 
impression on the broken blocks. The sharp-pointed splinters 
and the ragged edges of the vesicles are as untouched by weather 
as if they had just ceased forming. The two photographs accom- 
panying this paper, one a view of the side of the flow, the other a 
nearer view in the same locality, will vouch for what I have said, 
and will give a much better idea of the appearance than any 
‘description that I can write. 
The region for many miles on either side of the lava flow is a 
desolate one, almost destitute of water and inhabited only by the 
tanchmen, who here.and there have found a small spring at which 
they can water their cattle. Those who live in the vicinity are 
all of the opinion that the flow is a very recent one, and their con- 
clusion is, as I think I have shown, well founded. They base 
their conclusion upon still another bit of evidence, which I cannot | 
verify, since I have been unable to visit the locality. Without any 
‘personal evidence for or against it, I present the matter as it was 
told to me. The belief is that the lava has been erupted, if not 
since historic times, at least not long before the time of the Span- 
ish Invasion. It is believed that the lava flow has been the means 
of destroying a large and thriving Pueblo Indian town. Many 
reliable persons have told me of certain ruins, fifteen’ or twenty 
