'iRDLR'Kv] DISCOVERIES ATTEIBUTED TO EAELY MAN 15 



Professor Gregory's report (p. 29) throws an entirely new light 

 on the geological conditions in the Ayahuaycco gulch. He con- 

 cludes : 



It is unprofitable, from a geological standpoint, to work out the details of 

 erosional history in and about Cuzco, because of the extensive modification of 

 slopes and terraces resulting from cultivation and llood-water irrigation. How- 

 ever, the evidence indicating periodic destruction and building of terraces, 

 oven within the past 100 years, removes the necessity of ascribing great an- 

 tiquity to animal bones, parts of human skeletons, and fragments of pottery 

 found along stream banks and which may have been deposited on terraces or 

 on banks, or in the numerous small cave-like openings in the gravels, to be 

 transported, buried, or reexposed during alternating processes of deposition 

 and degradation. It is interesting to note that in the canyoned tributaries of 

 the Sappi and of sti'eams leading from the limestone plateau and from the 

 sandstone highlands bordering the Cuzco Basin on the south — valleys from 

 which terraces and slides have been removed and whose banks offered no 

 temptation to occupation, valleys whose present precipitous gravel wnlls are 

 clearly of glacial age — no traces of human occupation were revealed by carcrul 

 search. From these same gravels, however, mastodon bones h:ive been col- 

 lected, on the Huancaro and in the lower Cuzco Valley. The fact that these 

 bones from the Ayahuaycco gravels are of modern types . . . obviously cor- 

 roborates this view of depositional history, and also indicates important climatic 

 changes since the Spanish conquest. 



It will be noted that the explanations given in this paper are chielly of 

 negative value so far as arch.ieological research is concerned. That man 

 exi.sted in South America in glacial or preglacial times, and that the human 

 bones discovered in the Ayahuaycco Quebrada " appear to be from 20,000 to 

 40.000 years old " as tentatively held by Bowman, is not definitely disproven by 

 the field studies of the present writer. On the other hand, the geologic data 

 do not require more than a few hundreds of years as the age of the Inuiian re- 

 mains found in the Cuzco gravels. 



Dr. Eaton, in a further study of the animal bones found with the 

 remains of the '' Cuzco man/' succeeded, in the first place, in a definite 

 identification of the first rib, which looked like that of a bison, as that 

 of a cow of the kind raised on the elevated pastures about Cuzco, 

 w'hile the canine bones ma}^ be referred to a dog. 



The site of the discovery of the bones of the " Cuzco man '" Avas 

 carefully examined, and Dr. Eaton states : 



After studying the form and composition of the walls of the quebrada and 

 examining other deposits of bones both here and elsewhere in the Province of 

 Cuzco, I am led to the opinion that the bones excavated in 1911 were not origi- 

 nally embedded in the basal gravel of the spur at the time when that gravel 

 was itself in process of deposition, but were, in all probability, interred there 

 at a much later time when the northeast wall of the quebrada had assumed 

 more nearly its present contours. [P. 5.] 



In regard to the bones of lower animals accompanying these human remains 

 it seems to have been an ancient and common practice in this part of Peru to 

 place in the human grave pieces of the flesh of llamas and occasionally, if the 

 mute testimony of the bones can be relied on, a dog's entire carcass. There is 

 no reason to suppose that this ancestral custom would have been discontinued 



