THOMAS.] ALTAR MOUND. 131 



of a white material like ashes mixed with decayed leaves and grass. 

 Under these stones and resting on the natnral snrface of the ridge was 

 a thin layer of decayed vegetable matter {>■). The slopes i i surround- 

 ing the basin were of yellow clay similar to that of the thick upper 

 layer of the mound. The dark spots h and k indicate small fire beds. 



Partly under and partly in the bottom layer of decayed vegetable 

 matter and exactly in the center of the mound was a single skeleton (o) 

 lying on the back at full length, the feet to the south, but the head was 

 wanting. Not a tooth or particle of the jaw or skull was to be found, 

 though careful search was made. As all the other bones were well 

 preserved and comparatively sound, except that the pelvis and some of 

 the ribs were broken, it is presumed that the head must have been 

 removed before burial. This is the second instance observed in which 

 the head had been thus removed. The first was noticed at Pecan 

 Point, Arkansas. 



Six feet south of the center of the mound was a small deposit of 

 burned bones lying on the natural surface of the bluif. Seven feet 

 west ot the center, lying on the original soil, were the remains of an 

 infant (s), which had been doubled up until the knees touched the 

 chin, wrapped in a grass covering, and placed upon its left side. 



A seashell (Busycoii perversum) from which the cohimella had been 

 removed, converting it into a drinking cup, which was at the right 

 shoulder of the skeleton, and a fragment a])parently of another similar 

 shell, were the only relics found in the mound. The latter was in a 

 stone box or cist lii feet square and 1 foot deep, resting on the natural 

 surface of the ridge. Not a fragment of bone was found in this box. 



Another singular feature observed consisted of three small pits (», v, 

 x) under the eastern base of the upper layer. These were three holes, 

 from 15 to 18 inches in diameter and 1 foot deep. One of them con- 

 tained particles of rotten wood. There wcri' several intrusive burials 

 in the thick upper clay layer which presented nothing of special inter- 

 est. 



It would seem from the facts and figure given that we have in this 

 tumulus a specimen of the Ohio "altar mound" type, as what we have 

 called the nucleus or original mound is in fact one of the so-called 

 "altars" of the type described by Messrs. Squier and Davis. 



MADISON AND ST. CLAIR COUNTIES. 



On the line separating these t\\o counties is the celebrated Cahokia 

 group, which includes the giant structure known as the Cahokia or 

 Monk's mound. 



In the fall of 1882 Mr. William McAdams was engaged by this Bureau 

 to make an exploration and preliminary survey of this interesting re- 

 gion, but his work was suddenly cut short at the end of a month by 

 severe winter weather. 



