350 ON THE ANATOMY OF THE TODIES. 



halves of the separated portion fall asunder naturally, there being no 

 union either between the maxillo-palatines themselves (for the greater 

 part of their extent) or between them and the nasal septum, which here 

 does not appear at all in the roof of the mouth in this region. In the 

 Todies, though the septum thus appears, the maxillo-palatines are free 

 altogether both from it and from one another, apparently for their whole 

 extent *. If this is so, the Todies are not " Desmognatlice" and, inasmuch 

 as they lack the vomer altogether, cannot be included in any other of 

 Prof. Huxley's primary groups of Carinatae at all ! 



The vertebrae number 35, exclusive of the pygostyle, as already 

 correctly stated by Murie. Of these I reckon 15 as cervical, 5 dorsal, 

 8 sacral, and 7 caudal t. 



The close relationship of the Todidae to the Momotidae having been so 

 often urged by some of our best naturalists, it will be desirable to point 

 out succinctly some of the important points of difference between them. 



The Todidae, then, differ from the Momotidae, 



(1) In the non-union of the maxillo-palatines, these being attached in 

 the Motmots by harmonic suture. 



(2) In the lower margin of the nasal septum appearing in the roof of 

 the mouth between the free edges of the maxillo-palatines. In the 

 Motmots the nasal septum which ankyloses with the maxillo-palatines 

 anteriorly does not appear in the palate. 



(3) In the complete absence of a vomer, always represented in the 

 Momotidae by a small, but distinct, ossicle. 



(4) In possessing a well-developed lacrymal, quite absent (or early 

 ankylosed with the f rentals) in the Motmots. 



P. Z. S. 1882, (5) In the very slight development of the ascending plates of the 

 p. 448. palatines, well represented in the other group. 



(6) In the small amount of ossification in the interorbital septum, 

 this, in the Motmots, being nearly entirely osseous. 



(7) In the shape of the sternum, this having four distinct and deep 

 notches (the outer pair being far the larger) never converted into 

 foramina, and separated by delicate xiphoid processes. In the Motmots 

 the inner pair at least (Hylomanes), but usually both (Momotus, Bary- 

 phtlunyus, Eumomotd) are converted into smallish foramina. 



* It is impossible to state for certain how far anteriorly the maxillse extend, from 

 a study of the adult skull only ; but in Todus the osseous roof of the mouth is incom- 

 plete as far forwards as the anterior end of the unusually large nares, so that probably 

 it is only by the union of the dentary plates of the prsemaxillae that it is completely 

 ossified here. 



t Defining as " dorsal" all those, whether ankylosed to the sacrum or not, that bear 

 ribs united directly or indirectly with the sternum. Those that precede, whether or 

 not bearing ribs, are " cervical ; " those that follow, and are aukylosed together, are 

 " sacral," the remainder being " caudal." 



