18/2.] DR. J. MURIE ON THE SKELETON OF TODUS. 669 



mota exhibits a gradal disposition of the parts, which character is 

 heightened by the oblique truncation and posterior spineless nature 

 of the palatal plates, and the short pterygoid bars. But in this 

 genus and in Momotus the maxillo-palatines are mesially adnate, 

 whereas in the other Coccygomorphine groups compared the osseous 

 nasal septum less or more separates them. 



If we turn to the prsemaxillse, or what constitutes the beak, and for 

 obvious reasons examine its upper surface, we shall at once be able 

 to differentiate it from the whole of the Alcedinidse, and notice some 

 points allying it to the Momotidse and Meropidse. In the former 

 groups, without exception, the opposite bones rise high, and incline 

 towards each other with a well-defined ridge, sharp or rounder as may 

 be, and occasionally, as in Pelargopsis, with a decided culmen. In 

 Todus there is a most marked flatness, the bones exhibiting but a 

 very slight convexity in front of the nares, and that which divides 

 these orifices is limited to a low narrow rod or spicular bar. The 

 nostrils are each 0*3 inch long, straight, elliptical, and widely patulous ; 

 they are most like those of Dacelo as far as magnitude is concerned, 

 but, even relative to it, by far greater, and descend within a trifle of 

 the inferior premaxillary border. The oral surface of the praemaxillse 

 is uniformly flat, and the vascular sculpturing or furrows most 

 delicate. 



The descending branch of the nasal bone forms a small, obliquely 

 set ridge, surmounting the superior maxillary bone, and barely di- 

 stinguishable from it. The inner branch and the fillet anteriorly 

 bounding the fronto-maxillary hinge are both very narrow. Todus 

 is unlike the Alcedinidae and Momotidse, great and small, in the low 

 narrow ledging of the latter parts, and particularly in the way in 

 which the prefrontals impinge in a rounded abrupt manner. It is 

 this which gives the deep impression at the base of the nasal bones 

 alluded to by Mr. Eyton. 



In the size and shape of the narial orifices, lowness of depth, and 

 rounding of the upper surface of the prsemaxillse, Eumomota, Merops, 

 and some species of Picus have a cast towards Todus ; but the arch 

 of their nasal bones, relatively, is by far stouter ; their prsemaxillee, 

 again, are more bent at the tip than in it. 



The flatness, or wide shallow concavity of the prefrontals, which ob- 

 tains in most of the Kingfishers and Motmots, does not apply to Todus; 

 where each moiety is convex, the sagittal suture alone being represented 

 by a well-marked mesial furrow. The prefrontals altogether are narrow, 

 thus giving little interorbital breadth, which is even more strongly 

 pronounced by the smallness of the upright limb of each lachrymal, 

 which abuts against the anterior outer margin. Moreover this dis- 

 position produces a shallower appearance in the supraorbital incision, 

 which in reality is deeper and wider than in the Alcedinidae. As I 

 have intimated, the ascending frontals have a steeper gradient than 

 in the latter group, and the postfrontal region is in consequence more 

 elevated even than in Ispidina. 



Differentiation of the prefrontals &c. in some other groups I have 

 alluded to in speaking of the skull's contour superiorly. 



