292 Trans. Acad. Sci. of St. Louis. 



larity is so marked and so extensive at times that all the 

 spermatids of an antheridium are not only in the same stage 

 of development at one time, but often appear to develop 

 spermatozoids which are oriented in the same way in the 

 cell. 



I find the so-called "blepharoplast," or " Nebenkern," as 

 a round body lying outside the nucleus toward the center of 

 the cell, usually. It stains as the nucleoli within the nuclei 

 did before its appearance. Sometimes it is connected by 

 strands or fibers with the nucleus — more often such connec- 

 tion could not be demonstrated. The body, however, seems 

 to be present in all cases. It is noticeable that the nucleoli, 

 as distinct bodies, disappear before the appearance of this 

 body. At least I have not observed both as present at the 

 same time. This disappearance of the nucleoli at the time of 

 the appearance of the blepharoplast would suggest a relation- 

 ship between them, in material at least. Thej' stain alike. 

 The blepharoplast when first seen occupies a position which, 

 to say the least, could easily have been occupied by one of 

 the nucleoli before the nucleus left its position at the center 

 of the cell for the secondary position near the wall. Further, 

 the nuclear membrane, if it remains intact, has become so thin 

 that it is difficult to follow. Although I have not observed 

 its origin from the nucleoli, such a theory goes farthest to- 

 ward explaining the changes which occur. Such a theory, 

 coupled with the fact that it contains kinoplasm, as shown by 

 its function as a bearer of cilia, would agree with the con- 

 clusions of Strasburger ('97) as to the kinoplasmic nature of 

 the nucleolus. 



I cannot confirm the observations of Belajefi", Ikeno, and 

 Shaw, that the first step in the development of the spermato- 

 zoid is the stretching ( Ausdehnung) of this body first into a 

 crescent, then gradually into a fiber which forms a dark line 

 on the edge of the cytoplasmic anterior end of the sperma- 

 tozoid. I have observed it many times unchanged when the 

 nuclear portion of the spermatozoid had developed into a 

 whole spiral turn, and sometimes even more. Many of the 

 later stages of spermatogenesis and adult figures, as 

 figure 4, indicate that this body comes to lie at 



