SPERMATOGENESIS OF ASCARIS 433 
spermatozoa are represented which not only have lost all trace 
of the refractive body, but are entering eggs in this condition. 
In sections of one tube I found that nearly half the eggs hdd been 
entered by spermatozoa of this kind. To be sure that these were 
not merely lying upon the sections, I examined many whole 
eggs which had been fixed and stained just as the sectioned 
eggs were, and found many eggs which were being entered by 
such spermatozoa. I have examined a great many egg tubes and 
find them all alike with respect to this phenomenon (figs. 42 to 45). 
Probably no point in the study of Ascaris spermatogenesis has 
called forth greater difference of opinion than the nature and 
function of the refractive body. Van Beneden first observed 
spermatozoa entering eggs without it, and concluded from this 
fact that it plays no part whatever in fertilization. His further 
conclusion that its presence in the spermatozoon is purely acci- 
dental must be judged in the light of the fact that he had seen 
this structure only in the proximal region of the uterus, and 
thought it was formed there. 
Boveri agrees with Van Beneden that it is not necessary for 
fertilization, since this is accomplished with or without it. Sche- 
ben, on the other hand, believes it to be most important in fer- 
tilization, for he thinks it gives rise to the male pronucleus. 
Tretjakoff believes that its only function is to serve as a mechan- 
ical support for the sperm, corresponding in this respect to the 
capsule of the decapod spermatozoon as interpreted by Koltzoff. 
Romieu agrees to this suggestion, but adds that it may feed 
the egg as well as to help in effecting penetration. Romieu thinks 
that its presence is the sign of maturity of the sperm, and that 
it is present in every functional male cell. 
Marcus suggests that in Ascaris canis it may be a food supply. 
On page 460 we read, ‘‘Ich muss mich also in Gegensatz zu 
Scheben der Ansicht v. Benedens und Boveris ausschliessen die 
dem Glanskérper keine unmittelbare Bedeutung bei der Be- 
fruchtung zuschreiben. Nach meiner Auffassung ist er ein 
Nahrungskoérper. Ob die Dotterkugeln bei den Spermatocyten 
urspriinglich aus dem ins Plasma hinausgetreten Trophochrom- 
atin entstanden sind, kann ich nicht entscheiden.’”’ He adds 
