18 PROCEEDINGS OF THE NATIONAL MUSEUM. ^('1-. 57. 



Of the existence of a separate element in advance of the malleus it 

 may be said that there is a pointed spicule protruding under the upper 

 edge of the tympanic in the civets, apparently most distinct in 

 Paradoxurus, and in tlie otters among the Mustelines, which, from 

 what we have already seen in so many other species of mammals, 

 probably indicates its presence. I have not been able to determine 

 its exact relations with the processus gracilis in these forms. 



Primates. — Comparatively few of the reptilian elements described 

 in the foregoing pages are to be seen in the adult skull of the prmiates, 

 notwithstanding the embryological evidence seems to be very con- 

 clusive that they are to be seen in the early stages of development. 

 We thus find three centers of ossification for the m.alar; one for the 

 postorbital process of the frontal, one between the lachrymal and 

 frontal, and one alongside tlie nasal spine of the frontal. All these 

 centers of ossification can be easily interpreted on the basis of reptilian 

 anatomy. As we shall presently see, the malar foramen, which is 

 unusually large in some of the pruiiates, is like- 

 wise, in all probability, the vestige of an im- 

 portant opening in tlie reptilian skull. 



In studying the ossification centers of the 

 human malar I have found it very difficult to 

 distinguish the sutures separating them when 

 <?«'.o/^. gggjj from the outside, but when they are viewed 

 Fig. 11. -Homo sapiens, fj-^p^ ^.he inside they are much more evident on 



After ToLDT. /«., jugal; i i i> i ti 



Pst. o., postorbital; q«. accouut of the lack of scale-like overlappmg 

 ju., quadratojugal. ^p^j^ ^Yie inside of the arch. Evidence of the 



original separation of at least two of these pieces persists until as late 

 as the seventh month of fetal life, while from thS outside they always 

 appear to be fused by the end of the third month. I here reproduce 

 Toldt's figure (fig. 11) of the malar of a seventh month fetus, ^ which 

 shows this well. In the young stages the malar foramen is not 

 easily distinguished. There seem to be a number of openings through 

 the malar, some of which disappear as age advances. Just which one 

 of these finally becomes the malar foramen or foramina I have been 

 unable to determine with satisfaction, but it would seem that the fora- 

 men which remains is developed near the edge of the orbit and is 

 apparently not homologous with the large opening found in certain 

 other primates, notably in the spider monkeys, howlers, and teetes of 

 South America, and in some of the Madagascar lemurs. There seems 

 to be a great deal of variability in this opening among the primates. 

 The divided malar in tlie human skull, which occurs not infre- 

 quently as an anomaly, ^ represents the lower or quadrato-jugal ele- 

 ment of many mammals in which it remains distinct. In a young 



1 DieZerteilung des Jochbeines und andern Varietaten desselben, Sitzungsber. kais. Akad. Wissensch 

 Wien, 1903, pi. 1, fig. 5. 

 a See also AleS Hrdli6ka, Amer. NaturaUst, 1902-1904. 



