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moderately erecf, the fo-isa snhainiain is only indicated. The fora- 

 men aensticnm and higher npwards tiie I'oi'anien Kervi iaeialis 

 mark the border of the vestibnlar and eoeliiear parts; to the former 

 ai"e attached above the parietal plates ; they are vevj small and 

 insignificant. A foramen jngnlare spnrinm perforates its base. Froii- 

 tally they send ont a very short processns marginalis posterior, 

 exactly as in the monkey skull. On the exterior of the ear-eap- 

 sules lie, in exactly the same way as I described for the mole and 

 embryos of apes, the cartilaginous stirrup, an\il and hammer, pas- 

 sing into Meckel's cartilage. 



The orbito-temporal part is characterised by its relatively pheno- 

 menal length. The continuation of the cranial trabecle from the 

 saddle groo\'e, where it had much broadened, is a narrow high 

 ridge, a true septum interorbitale (Gaupp) still more extended than 

 I found it with apes, although not so high as there. So the cranium 

 is clearly tropibasical. By this long se[>tum, which in front of course 

 passes into the nasal septum, the nasal capsule is far separated 

 from the brain capsule; it lies far in front of it, exactly as with 

 Reptiles. The relatively large eyes of Tarsius are probably the cause 

 of the survival of this extremelj' primitive formation. 



Where the described cartilaginous beam broadens into the hypo- 

 physis groove it sends out, fairly deep towards the base, a round 

 stalk at each side, bearing the small ala temporalis, which tapers 

 in the same way as with the foetus of man and ape. It does not 

 serve as a cranial wall yet, and has no Foramina rotunda and ovalia 

 yet. Above it starts with two roots the large ala orbitalis. Between 

 the roots the two foramina optica, the right and left one, are very 

 close together, so that only the thin septum mentioned separates 

 them. The orbital wings, themselves large plates, are neither bent 

 upwards so strongly as with the lower mammals (the mole), nor 

 do they extend laterally in such a perfect plane as with ape and 

 man, but their shape is exactly between the two extremes, they 

 slant sideways and upwards. Also the circumstance that their pos- 

 terior end lengthens out into a real, although \ery thin taenia 

 marginalis, which nearly reaches the parietal plate (there remains a 

 very small gap), shows a similar transitional stage between the 

 Primates and the other mammals. The anterior parts of the alae 

 orbitales are not connected with the nasal capside as usual (also in 

 the sheep e. g. this connection is wanting according to Decker). 

 Below the sphenoid beam are, isolated from it, the roundish ptery- 

 goid cartilages, quite independent. 



Proximally the septum interorbitale, as has been stated, passes 



