MUNIZ—MC GEE] OPERATION BY RECTILINEAR INCISION Dill 
The supplementary incision is about 20 mm. below the aperture, near 
the center of the anterior part of the left parietal, and nearly parallel 
with the more nearly longitudinal incisions of the principal operation. 
It is precisely like the main incisions, V-shape in section, 42 mm. long, 
5mm. wide, and 6 mm. deep toward the center, where it does not quite 
penetrate the inner table of the skull, narrowing and shallowing gradu- 
ally toward the extremities. Just below its center there is a transverse 
seratch (hardly visible in the plate), apparently marking a transverse 
incision barely started when this part of the operation was abandoned. 
There is a similar faint scratch back of the main aperture, between and 
behind the main longitudinal incisions, and approximately parallel with 
them, which appears in the reproduction. 
The preservation of the specimen is so perfect as to reveal even the 
faintest scratches produced in connection with the operation, and thus 
to indicate the character of the instrument and the mode of its use. 
The scratches, both random and atthe ends of some of the incisions, 
show that the instrument had a single moderately sharp point, thicken- 
ing rapidly to 5 or 4 mm. within 6 or 7 mm. from the tip; that not only 
the point but the sides bit into and ground away the bone as it was 
manipulated; and that the manipulation could only have been a recipro- 
cal motion back and forth from end to end of the incision, accompanied 
by considerable pressure. It is noteworthy that no known metal instru- 
ment or implement would produce the general and special features of 
the incisions in this eranium, while all the features of incisions and 
scratches are precisely such as would be produced by a sharpened stone 
in the form of a spearhead, arrowpoint, or knife. 
In addition to the operation and supplementary incision, the cranium 
displays a few significant marks. The most conspicuous of these is 
almost exactly in the center of the frontal bone, some 40 mm. above 
the orbital ridges; it is a narrow, longitudinal contusion, 20 mm. in 
length, along which the bone is crushed irregularly, in such manner as 
to indicate impact of a moderately sharp but rough-edged instrument, 
the force of impact being such as to produce a curvilinear crack in the 
outer table, nearly parallel with the contusion, and joining it at the 
ends. The appearance of this lesion indicates that it was produced 
during life, though there are no marks of reparative process. Near the 
left margin of the frontal bone, some 50 mm. above the left orbit, there 
are two deep grooves 2 or 3 mm. wide and 15 mm. and 20 mm. long, 
respectively, partly obliterated by reparative process, evidently marking 
old wounds. (The three marks are concealed beneath the label.) 
For comparison with the Muniz specimens, a photomechanical repro- 
duction of the “Inca skull,” brought from a cemetery in the valley of 
Yueay, Peru, by E. G. Squier, is introduced in plate 111, from a photo- 
graph taken in the United States Army Medical Museum.! The oper- 


1A wood engraving from this photograph forms plate vil of Dr Fletcher’s memoir ‘‘On Prehistoric 
Trephining and Cranial Amulets,” cited above. A wood engraving of the same skull appears on 
_p. 457 of Squier’s ‘‘ Peru—Incidents of Travel and Exploration in the Land of the Incas.’ 
