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brains, in which the other principal sulei had not yet reached their 
full development, so that the question remains whether not a transi- 
tory sulcus was present. Rerzius too takes it in that way (s. desevip- 
tion Plate XIII). 
Excepting Ecker and Rerzius, I could not find, reading through 
other literature, anything that indicates a fissura simialis in human 
embryos either. 
The only exception might have been the report of KonLpruaer ,), 
who writes on p. 243: “Die Affenspalte beim Menschen halte ich 
also für eine im embryonalen Leben sich bildende Anomalie”. This 
would mean, that he has found in the unborn fruit a suleus, which 
should be taken for an ape fissure. As I could not find in the com- 
munications written by KOnrLBRUGGE anything more in particular 
about this sulcus, and the question is of great importance, I addressed 
him personally and I received the answer, that he himself never saw 
such a suleus in human foetus, but from analogy with what was 
found in apes, he did not want to exclude the possibility, that in 
man, during foetal life an ape fissure might be formed. 
Summarizing what previously has been said, one must come to the 
conclusion that the study of the human embryos and foeti does 
not teach us anything about the commencement of the ape-fissure. 
If one holds to the analogy in development of the sulei in men 
and apes, “then the above said would suffice to conclude that in man 
no ape fissure is formed. 
This consequence therefore presents itself, because we know, — in a 
previous report I called attention to it?) —, that the ape fissure in anthro- 
poids is already much less developed than in semnopitheci and macaci. 
It is therefore not strange in itself, that in human brains, which 
in the range of development are placed much higher than those of 
the anthropoids, the ape fissure does not come to development. 
However while even' in recent years Error SMITH and others 
have defended the conviction, that in man an ape tüssure is 
surely found, I will accept for a moment, that the fissura simialis, 
contrary to the other principal fissures, is formed in man only after 
foetal life. 
And I will accept this the sooner, as I showed sub d and e, that 
in the different ape species, this sulcus can be formed at different 
places and that the characteristics of these different sulci, need not 
be the same. 
The possibility therefore is not, theoretically spoken, excluded that 
in man this fissura is formed under totally different circumstances, 
e.g. only after foetal life. 
