Dr. J. Murie on the Moimots and their Affinities. 393 



joining, so that the spaces are not deprived of the character of 

 foramina. Keel and rostrum as in Momotus, but the costal pro- 

 cesses are proportionally a trifle shorter. Relatively and abso- 

 lutely the coracoid of Eumomota is shorter, being subequal to 

 the oblique sternal diameter j the epicoracoid is broader, and 

 the shaft a grade stouter. The scapula posteriorly tends to 

 increase of curvature. 



The beak is exactly of the same length as in M. lessuni ; the 

 latter bird, therefore, has a preponderance in long diameter of 

 the orbito-occipital regions. The premaxillary depth is less in 

 the first, particularly the culmen. Although in Eumomota the 

 breadth of the beak seems greater than in Momotus, this only 

 applies to its anterior half; for in the latter genus its basal seg- 

 ment is decidedly widest. In the former the nostrils come 

 further back or cut more into the nasals. Its horizontal palatal 

 plates are altogether narrower. The breadth of the frontal be- 

 tween the orbits is alike in each genus — therefore, other things 

 being equal, relatively widest in Eumomota. As in the posterior 

 or cerebral segment there is little diflference of fore and aft 

 length between the two forms, it follows that the mid or orbital 

 segment of E. superciliaris is the chief part wherein curtailment 

 of the skull is effected. Momotus undoubtedly has the wider 

 skull occipitally ; but the antero-posterior diameter of this part 

 is little, if at all, over what obtains in Eumomota. 



The mandibular length in the last mentioned is 2"15 inches ; 

 of this, the shallow symphysis front-joining portion is 0*85 inch. 

 The bone altogether is low or shallow, and with a slight curva- 

 ture corresponding to the beak-deflection. There is no so-called 

 " dentary space " or median fissure, this being obliterated by an 

 ossific plate. The inner and posterior mandibular angles are 

 each well marked. 



The only appreciable change of pelvic formation from M. ru- 

 ficapillus is in the prseacetabular being a shade longer than the 

 postacetabular region ; and there is a small foramen in front of 

 the hip-joint or acetabular perforation. 



Concerning the shape of the bones of the extremities, what 

 has been said of the preceding type applies in this case. Pro- 



SER III. VOL. II. 2 F 



