No. I.] SPERMATOGENESIS OF BATRACHOSEPS. 85 



for the mantle fibers, for the retractile fibers, and for the new- 

 cell wall. This material is both in the form of secretions and 

 actual protoplasmic granula. The form of the spheres is not 

 permanent. Each one of the spheres at times dissolves, again 

 to reappear, the granules being the only permanent elements 

 of the spheres. The alveolated structure of the spheres is due 

 to metaplasmic secretions from the granules composing the 

 sphere. The granules of the plasmosphere, and especially 

 those of the granosphere, have a great affinity for congo, and 

 by the use of this stain they may be recognized even when 

 dispersed in the cytoplasm. 



III. The cytoplasmic membrane, or false nuclear wall, 

 around the nucleus at the end of the anaphase, is formed by a 

 condensation of cytoplasmic granules, and is not a true nuclear 

 membrane. It is dissolved as soon as its usefulness is past. 

 Its purpose is to allow the formation of a large vacuole around 

 the nucleus, in order that the latter may be able to enter a stage 

 of growth without hindrance from the surrounding cytoplasm. 

 This cytoplasmic membrane forms the base upon which are 

 formed the fiber cones for the pulling away of the membrane. 



IV. The chromioles are the most minute, individualized, and 

 the most permanent elements of the chromosomes which we 

 can perceive with our present optical means. They are sub- 

 ject to division and growth, but are probably otherwise con- 

 stant. There are generally six of these chromioles in every 

 chromomere ; and as there are six chromomeres in every per- 

 fect chromosome, we have thirty-six chromioles in each chro- 

 mosome of the metaphase of the auxocyte. The formation 

 of the chromosome commences with the formation of a chro- 

 momere with from three to six chromioles, according to the 

 variety of the cell. A number of such chromomeres are con- 

 nected together to form a leader, the leader is finally contracted, 

 splits, and divides, after which each half further contracts, and, 

 after separation by equation division, forms a chromosome in 

 the anaphase. The chromomeres and chromosomes are only 

 temporary structures, the purpose of which is to facilitate and 

 to make possible the arrangement, the nourishment, and the 

 division of the chromioles. The chromioles, being the most 



