No. 6.— Results of the Yale Peruvian Expedition of 1911.— The 
Arachnida. 
By Ratexw V. CHAMBERLIN. 
THE arachnids, upon a study of which this paper is based, were 
collected for the most part by Prof. H. W. Foote while a member of 
the Yale Peruvian Expedition of 1911. The collection has proved to 
be extraordinarily interesting, presenting a very large proportion of 
previously undescribed forms among which are eighty-two new species 
and twelve new genera. A few specimens were secured at Panama; 
but aside from these, the material all comes from localities in a little 
known section of southeastern Peru at elevations ranging from 3,000 
to 11,500 feet above sea level. Comparatively few of the species 
seem to be identical with forms recorded from more northerly locali- 
ties of Peru by Taczanowski in his Les Araneides du Peru (Bull. Soc. 
nat. Mosc. 1878, 53, p. 278-374; Horae Soc. entom. Ross., 1878, 14. 
p. 140-175; 1879, 15, p. 102-136). Some of the localities mentioned 
are not on published maps. 
This collection of arachnids was turned over to the author for study 
through the kindness of Professor Foote, who has also consented that 
the entire lot remain the property of the Museum of Comparative 
Zoology. Prof. A. Petrunkevitch of Yale had planned to report 
upon the collection but the press of other duties prevented. He had 
made notes and drawings of several species which were kindly sent 
to me. 
The principal Peruvian localities from which the arachnids of the 
collection come with elevations and months during which specimens 
were secured are as follows: — 
Arequipa, 7,600 feet June 
Cuzco, 11,500 feet July 
Huadquina, 5,000 feet July 
Ollantaytambo, 9,000 feet July 
Torontoy, 8,000 feet July 
San Miguel, 6,000 feet July 
Urubamba, 9,500 feet July 
Lucma, 7,000 feet August 
Paltaybamba, 5,000 feet August 
