12 BUREAU OF AMERICAN ETHNOLOGY [boll. 70 



mounds near his ranch. As no name was given this village it is here 

 called the Mitchell Spring Village. Morgan likewise mentions the 

 ruin at Mud Spring and a tower in the ruin near his spring. Professor 

 Newberry was the first author to affix the name Surouaro to a ruin 

 situated at the head of the Yellow Jacket Canyon. 



Several of these ruins were described and figured by Mr. Warren K. 

 Moorehead as "The Great Ruins of Upper McElmo Creek" in the 

 Illustrated American for July 9, 1892, the sixth of a series of articles 

 under a general title ''In search of a Lost Race." He gives descrip- 

 tions of a " cave shelter ' ; found near Twin Towers, Square Tower in 

 "Ruin Canyon," a building (Hovenweep Castle), and the tower at 

 the junction of the North and South Forks of Ruin Canyon. This 

 paper is accompanied by a map of Ruin Canyon by Mr. Cowen. In 

 Mooreh end's discussion of these remains, individual towers and other 

 ruins are designated by capital letters, A-V, to some of which are 

 also affixed the names "Hollow Boulder," "Twin Towers," "Square 

 Tower," etc. Details of structure and measurements of the more 

 striking buildings and a discussion of certain features of structure, 

 some of which will be considered later under individual ruins, are 

 likewise given. 



The most important general article yet published on the prehis- 

 toric remains of the region here considered is by Dr. T. Mitchell 

 Prudden, 1 who also mentions several of the ruins here treated. His 

 most important contribution is a description of what he calls the 

 "unit type/' which he recognized as a fundamental structural 

 feature in the pueblos of this region. He also showed that the kiva 

 in Montezuma Valley villages is identical with that of cliff-dwellings 

 in the Mesa Verde, and emphasized, as an important feature, the 

 union of the tower and the pueblo, a characteristic of the highest 

 form of pueblo architecture. 



Doctor Prudden has followed his comprehensive paper above 

 mentioned with an account 2 of the excavation of one of the mounds 

 at Mitchell Spring in which he adds to our knowledge of the structure 

 of his "unit type." 



In "A Further Study of Prehistoric Small House Ruins in the San 

 Juan Watershed," 3 Doctor Prudden has furnished important addi- 

 tional data which shows the uniformity of the unit type over a 

 large area of the San Juan drainage. 



The following among other prehistoric remains in the district 

 mentioned or described by Doctor Prudden are covered by the 

 author's reconnoissance: 



1 The Prehistoric Ruins of the San Juan Watershed in Utah, Arizona, Colorado, and New Mexico., 

 Amer. Allthrop., n, s. vol. v, no. 2, 1908. 



*The Circular Eivas c>r Small Ruins in the San Juan Watershed. Amer. Anthrop., n. s. vol. xvi, no. 1, 

 1914. 



3 Memoirs Amer. Anthrop. Asso., vol. v, no. 1, 1918. 



