2o6 Bulletin American Museum of Nattcral History. [Vol. XIX, 



constricted between the inner and outer cusps than in any de- 

 scribed Leptictid ; cusps somewhat higher and last molar less 

 reduced than in any later species. 



No. 9604, a fragmentary skull and jaw, with humerus, 

 radius, two phalanges, and a caudal vertebra, exhibits most of 

 the permanent dentition well preserved. 



Upper jaw. — Incisors not known. Canine of moderate size, com- 

 pressed, somewhat ridged externally, with no indication of the in- 

 cipient heel seen in 

 Palcsictops. P' one- 

 rooted, smaller than 

 canine. P^ two-root- 

 ed, compressed, with 

 small posterior basal 

 cusp or heel. P3 three- 

 rooted, with strong, 

 well-separated de, 

 higher but less sep- 

 arated tr, and minute 

 antero-extemal basal 

 ci\sp ; the protocone 

 much overtopping the 

 other cusps. P'^ mo- 

 lariform, but tr not 

 yet as high as pr, de 

 equalling pr in height , 

 .small hy, and strong 

 protostyie. First and 



Fig. 4. Ictops ncntidens. Teeth, twice natural size. A, 

 crown view of upper teeth ; B, external view of upper and 

 lower teeth. No. y6o4, the lower molars from No. 9605. 



second molars with pa 

 and nie of equal size, hy better developed than in p^, a small protostyie 

 on m'. M3 with reduced me and rudimentary hy. All molars and 

 p'* wide transversely, with some con.striction between inner and outer 

 cusps. M3 smaller than m' and m^, but not so much reduced as in the 

 later species. 



Lower jaw. — Dental series continuovis without diastemata. Three 

 small incisors. Canine small, incisiform, somewhat larger than in- 

 cisors. Pi one-rooted, p, two-rooted, pj two-rooted, compressed, 

 with anterior and posterior cusps and small heel. The lower molars 

 are not preserved in this specimen. In No. 9605 m, and m^ are pre- 

 served; the trigonid is high, composed of two equal well-separated 

 cusps, talonid much lower, bearing three posterior cusps, external, in- 

 ternal, and postero-median respectively, well separated from the 

 trigonid but not from each other. M, is a little longer than m, but 



