28 ELEMENTS OF MAMMALIAN ANATOMY. 
of the sense of smell is proportional to the development of 
the ethmoturbinals. In most orders of animals five scrolls 
are present, but in Echidna there are six and in some Ungu- 
lates there are eight, while in adult Primates there are only 
from one to three, more, however, being present in the 
embryo. 
The mesethmoid is the perpendicular plate of bone which, 
prolonged craniad by cartilage, separates the nasal cavity 
into two portions. Caudad it is united to the cribriform 
Fic. 16. Dorsat Asprct oF THE Cat’s SKULL. 
ap, Anterior palatine foramen; c, canine tooth; co, coronal suture; f, 
foramina in palatine bone, the lateral one is the posterior palatine 
and the medial one is the sphenopalatine; fr, frontal; if, infraorbital 
foramen; in, interparietal; /c, lachrymal canal at the medial border 
of the lachrymal bone; /d, lambdoidal crest; ml, malar; mx, maxil- 
lary; na, nasal; oc, occipital; », vertical plate of the palatine; po, 
postorbital process of the frontal; pm, postorbital process of the 
malar; par, parietal; px, premaxillary; sq, squamosal part of the 
temporal; sg, sagittal suture; sp, alisphenoid part of the sphenoid; 
tp, temporal fossa; zg, zygomatic process of the squamosal. 
plate, dorsally it articulates with the median descending 
plates of the frontals and the nasals, and ventrally it articu- 
