No. I.] SPERMATOGENESIS OF BATRACHOSEPS. 91 



a bouquet. This stage contains the three substages mentioned 

 below (Figs. 12-15). 



Bouquet Stage with Twisted Segments. — The spireme seg- 

 ments are about one-third longer than the diameter of the 

 nucleus. Many small chromomeres (Fig. 12). 



Bouquet with Split Segmejits. — The chromomeres are dis- 

 tinctly split, but are not yet separated (Fig. 15). 



Bvetzel Stage. — The segments have the form of bretzels or 

 twisted rings. These bretzel-shaped chromosomes may be 

 more or less regular, and their ends may only overlap each 

 other, or they may be actually grown together (Fig. 25). 



Central Spindle. — The primary spindle by which the archo- 

 somes are united, and which form the center of the mitotic 

 figure. It does not include the contractile fibers attached to 

 the chromosomes, nor the mantle fibers. The spindle which 

 connects the two poles (Hermann, Figs. 49-56). 



Centriole. — The innermost dark-staining granule or granules, 

 situated in the center of the archosome, and also in the acces- 

 sory archosome. It does not include the somosphere. 



Cetitrosome. — On account of the many and various defini- 

 tions given by respective investigators, this name has recently 

 been discarded by several investigators, among them by W. 

 Flemming, who substitutes the word Centralkdrper. But while 

 we are told that this word expresses the same thing as the word 

 " centriole," we are yet at a loss to know if it includes the somo- 

 sphere, or the somosphere and centrosphere. When the word 

 "centrosome" is used in this paper, it is always left open and 

 undecided whether we have before us an archosome or an acces- 

 sory archosome. I use this word only to indicate a centriole 

 surrounded by its somosphere. 



Centrosphere. — The more or less hyaline and indifferently 

 stainable zone surrounding the somosphere and centriole, the 

 outer sphere of the archosome, as well as of the accessory 

 archosomes. It is sometimes amoeboid, sometimes again cir- 

 cular or globular, with a perfectly even outline. It is princi- 

 pally an organ of locomotion. 



Checkerboard Stage. — The second prophase of the sperma- 

 tocyte. The chromomeres have separated and scattered over 



