1041 
ZUCKERKANDL strongly emphasizes a difference between monkey- 
slit — i.e. the slit between the operculum occipitale and the parietal 
convolution lying frontally to the operculated transition-convolutions 
-— and the monkey-slit suleus — i.e. the sulcus lying on the bottom 
of the sulc. lunatus. 
This difference must unconditionally be accepted, and to my 
knowledge this is done by the majority of authors (Bork a.o.). 
It is however another question whether this difference is really 
of such a nature that we should be compelled by it for ever to deny 
the homologisation between a monkey-slit and a very similar 
sulcus in man. For that similarity is even readily accepted by 
ZUCKERKANDL, as he admits the occurrence of “Affenspaltresten” in 
man. Error SMITH is of opinion that the difference is nothing 
but a quibble of words. Evidently the matter hinges upon the 
question: what is in the monkey-slit-complex the cardinal point? 
We have then the choice between the s/t — postulating the existence 
of bottom-convolutions and an operculum covering these — and the 
suleus existing on the bottom of the slit, which if there are no 
bottom-convolutions to be opereulated, looks like every other sulcus. 
In lower monkeys (platyrrhines) and prosimii’) a suleus is found 
that must doubtlessly be indicated as suleus lunatus whilst bottom- 
convolutions, operculation, a proper ““monkey-slit’®) may be absent. 
This suleus lies in the brains uf these animals transversally — 
often not reaching the interhemispherical fissure — across part of 
the latero-dorsal surface of the lob. occipitalis. No other sulcus ends in it; 
it lies occipital from the suleus parieto-occipitalis. In some platyr- 
rhines (ateles) the sulc. interparietalis (which, as has been remarked, 
does not reach the sulc. lunatus) forms a 7-shaped extremity, some- 
times already indicated in some specimens of lemuridae. I refer 
those interested in this problem to the report that will be given by 
Dr. Ariers Karpers in 1913 at the International Congress of Medicine 
in London: Cerebral localization and the significance of sulci. 
Ascending in the range of monkeys we find that the sule. inter- 
parietalis in katarrhines has its distal termination in the s. lunatus. 
At the same time we find that, at the bottom of the latter, cortical 
convolutions are hidden; its occipital lip has grown an operculum. 
The most developed katarrhines — the anthropoides — usually 
1) ZieneN, Ueber die Grosshirnfurchung der-Halbaffen Arch. f. Psych. Bd 28 
S. 898. 
2) KükENTHAL u. ZIEHEN, Untersuchungen über die Grosshirnfurchen der Primaten ° 
Jenaische Zeitschr. für Naturwissensch. Bd. 29, S. 1. 
For further literature vide ARIENS KAPPERS (lI. ¢.). 
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