No. I.] SPERMATOGENESIS OF BATRACHOSEPS. 79 



most highly organized cells. With proper differentiation by 

 means of stains and differentiating light we find that the gran- 

 ules are not mixed promiscuously, but are placed alongside of 

 each other in a most regular manner. There is no trace of any 

 fibers nor of any alveolar or foam structure (Wabenbau). The 

 chromioles are suspended singly on fine threads which are made 

 up of other granules of a linin and chromoplasmic nature. 

 Almost every one of these granules can be seen, and the 

 majority can actually be counted. 



If we again turn to the linin network, which also is evenly 

 spread out between the chromioles, we also find that the indi- 

 vidual threads and meshes of this network are composed of reg- 

 ular granules of uniform size and general appearance. This 

 refers also to the linoplasts, which are principally composed of 

 granules, as far as I can make out, of exactly the same size, form, 

 and nature as the linin granules of the network. We have thus 

 accounted for the two principal structures of the nucleus. The 

 chromoplasts are generally so intensely stained that their finer 

 structure is often obscured, but in favorable places we see that 

 even they are composed of smaller granules of various sizes. 



If we now turn to the cytoplasm proper, we find even more 

 readily that it is composed of granules which at first appear 

 to vary, but which, when more closely studied, are found to 

 be uniform in size. This refers only to those which are 

 stained and differentiated in the same manner. In places 

 where we meet with larger globules a closer scrutiny will dis- 

 close the fact that these are only accumulations of the general 

 granula of the cytoplasm. Of the cell wall I have made no 

 special study. Of the cytoplasmic membrane forming around 

 the new nucleus the structure is quite plain. It is composed 

 of granules of the same size and color as the cytoplasm, so 

 closely situated as to be practically continuous. In another 

 place I have already referred to its probable derivation from the 

 cytoplasm. With the nuclear membrane the case is very much 

 the same, it being composed of granules resembling those of 

 the linin network. 



If we now examine into the nature of the fibrous structures 

 so often appearing in the cytoplasm proper, especially outside 



