MUNSON: SPERMATOGENESIS OF PAPILIO. 
109 
the rest of the cell being precipitated much as crystals are formed. 
Our present conception of the cell dates from 1860 when Max Schultze 
gave us our present definition of a cell. Even as late as 1885, Kolliker 
seems to have believed that the head of the spermatozoon proceeds 
from one part of the nucleus and the tail from another part of it. 
On the other hand, it was maintained by many at that time that 
the nucleus disappears and has nothing to do with the formation 
of the spermatozoon. Zenker thought that to be true in the case 
of isopods, and Remak ( 54 ) at about the same time thought it true 
also of amphibians. A similar view was held by Metschnikoff (’68) 
in the case of crayfish, and bv Balbiani (’ 69 ) in the spermatozoa of 
Aphis. The spermatozoon of amphioxus was thought by Langer- 
hans (’ 76 ) not to develop from the nucleus, but from a body at the 
side of the nucleus possibly what we now know as the nebenkern. 
Says Sabatier (’ 90 ): u Les grains de nucleine du noyau deviennent 
vesiculeux et forment une groupe de vesicules dites nucleaires, qui en 
se fusionnant et en perdant leur affinite pour les colorants nucleaires, 
constituent la coiffe cephalique en forme d’anere. Elies represented 
ce qui reste du noyau qui s’est done altere et a perdu ses caracteres 
nucleaires. La degenerescence du noyau comme noyau est done 
un des traits principaux de la spermatogenese des Locustides.” 
On the other hand, Bessels (’ 67 ) speaking of Lepidoptera (the forms 
related to the subject of the present work) says: “Wir haben es hier 
mit einer bildung der spermatozoon aus den zellkerns zu thun deren 
entstehung ausserhalb der kerneliegenden theile des zelleninhalts wie 
das Weismann vermuthet, ich in, abrede stellen muss.’’ 
We thus have had what might be called respectively the nuclear 
and the cytoplasmic view of sperm formation. But several early 
observers were able to show the presence of the nucleus in the sper¬ 
matozoa supposed to be devoid of them, thanks, doubtless, to 
improved methods and technique. Nussbaum (’ 84 ) and likewise 
Gilson (’ 85 -’ 88 ) showed the presence of the nucleus in Crustacea. 
But even considerably earlier than these discoveries, our present 
view with regard to the function of the nucleus and cytoplasm was 
not without its advocates. Among the first to insist on the presence 
of both nucleus and cytoplasm in the formation of the spermatozoon 
was Henle (’66). Even as early as 1865, Schweigger-Seidel (’66) 
concluded that the spermatozoon is an entire cell which has merely 
been transformed. It is interesting to note that he even made out. 
