146 BULLETIN OF THE 



In the peccary,* Dicotyles torguatus (Plate III. figs. 1 - 3), the encra- 

 nial surface is uniformly concave, and presents scarcely any angulation 

 inferiorly. Hence, the indications of separation of the ectoturbinals 

 from the endoturbinals are indistinct. The basal aspects of the endo- 

 turbinal plates form -well-defined lines on the cribriform plate, about 

 which are arranged a number of little pits. From the bottom of these 

 lie the foramina of the olfactory nerves. The most conspicuous of 

 these is the one for the first eudoturbinal plate. The septoturbinal sur- 

 face is on a higher plane than that of the ethmoturbinals. The crista 

 galli is distinct throughout. The non-perforate space is nearly one third 

 the length of the cribriform plate. Of the nasal surfaces, it is seen on the 

 frontal section that the divisions between the ectoturbinals and the endo- 

 turbinals are well defined. The former are seen to have a less compli- 

 cated structure, and are arranged as converging radii from the upper and 

 lateral walls. The endoturbinals are arranged in tiers, and constitute, 

 with the median exposure of the nasoturbinal, the entirety of the me- 

 dian surface. 



The ectoturbinals are nine in number. The first ectoturbinal and 

 the nasoturbinal are confluent. The former presents a convex uniform 

 surface above. The nasoturbinal is distinct from the meso-ethmoid. 

 The second ectoturbinal is of the same size as the first, but more dis- 

 tinctly biconvolute at the base. The third is the longest of the ecto- 

 turbinal series, and reaches the centre of the ectoturbinal space. Three 

 additional plates, rudimental in character, are seen on the lateral aspect 

 of the section. The endoturbinals are also niue in number, four of 

 them only reaching the median sm-face. They are much more convo- 

 lute than in the ectoturbinals, and present a number of secondary folia. 



The sphenoturbinal is seen distinctly united to the meso-ethmoid. 



In the two-toed sloth, t Chola-pa* <litl<irt i/lus (Plate 111. figs. 5, 6), the 

 cribriform plate is without angulation, as seen in the skull of the young 

 of this species, and the entire surface which answers to that fur endo- 

 turbinals is marked by four plates and associated foramina. The plates 

 are all united anteriorly into a single transverse lamina. The posterior 

 non-perforate space equals in longitudinal diameter one third of the 

 area of the cribriform plate. The septoturbinal space is scarcely raised 

 above the plane of the turbinal spaces. The crista galli answers in 



* For purposes of comparison, the encranial surface of the ethmoid bone <>f the 

 hog i> figured (Plate III. ti:_'. I), bul not described. 



t For purposes of comparison, the encranial -mil the nasal surfai 

 are presented in Bgs. l ami 2 of Plate IV., bul not here described. 



