225 
there it may be accepted, that also in the adult state no fissura 
- simialis appears. 
5. The suleus lunatus, described by Error Smita, for the rest 
possesses no properties which characterize it as an ape fissure. 
6. The suleus lunatus therefore is nothing but an ordinary sulcus 
or confluence of a few of them, by which a pseudo-operculum arises, 
thus a “Halbringform” in tbe sense of Rrraztus. 
1. Kontprueer, J. H. F. Die Variationen an den Grosshirnfurchen der Affen 
mit besonderer Berücksichtigung der Affenspalte. Zeitschr. f. Morph. u. Anthrop. 1903. 
2. Id. Die Gehirnfurchen der Javanen. Verhandelingen der Koninkl. Akademie 
v. Wetenschappen te Amsterdam. 1606. 
3. Smitn, J. Extior. The so-called ‘‘Affenspalte” in the Human (Egyptian) Brain. 
Anatomischer Anzeiger 1904. 
4. Hursnorr Pot, D. J. The fissura simialis in embryos of semnopitheci. These 
Proc, XVID p. 1571. 
5. Id. The relation of the plis de passage of GRATIOLET to the ape fissure. 
These Proc. p. 104. 
6. Ecker, A. Zur Entwicklungsgeschichte der Furchen u. Windungen der Gross- 
hirn-Hemisphären im Foetus des Menschen. Archiv f. Anthropologie. 1868. 
7. Rerztus, Gustar. Das Menschenhirn. Stockholm. 1896. 
8. Suita, G. Extiot. The morphology of the Occipital Region of the Cerebral 
Hemisphere in Man and the Apes. Anat. Anzeiger. 1904. 
9, ZuckeRKANDL, C. Zur Morphologie des Affengehirnes. Zeitschr. f. Morph. u. 
Anthrop. 1903. 
10. Mureny, J. B. Note on the sulcus lunatus in negro and white brains and its 
relation to the area striata. The anatomical Record. 1910. 
11. Bropman, H. Histologische Lokalisation. Journal für Psychologie und Neuro- 
logie. 1905— 1906. 
Physics. — “The currents arising in n-coupled circuits when the 
primary current is suddenly broken or completed.” By Batu. 
VAN DER Por Jr. (Communicated by Prof. W. H. Jurmus.) 
(Comraunicated in the meeting of January 29, 1916.) 
Suppose we have two circuits with given resistance and selfin- 
duction and coupled magnetically. If the electromotive force in one of 
the circuits suddenly stops, the current in it will asymptotically fall 
to a zero value, whereas the current in the other circuit rises from 
zero to a maximum value, then gradually falling again to zero. 
This paper will treat on the following extension of this problem: 
1. The change in time of the currents excited in 7 equal circuits 
coupled magnetically, in such a way that the first is coupled with 
the second, the second with the third, ete, the m—1' with then. 
15 
Proceedings Royal Acad. Amsterdam, Vol. XIX. 
