370 MONTGOMERY. [Vol. XV. 



associations de granules provenant de la desagregation de 

 I'element nucl^inien " ; and then follow the "nucleoles ter- 

 tiaires," which differ from the nucleoli of the preceding two 

 generations in that they do not come from degenerating gran- 

 ules of preceding generations, but are detached from them in 

 the form of spherules. Each nucleolus of each generation 

 arises, increases in size, becomes more complex in structure, 

 and then passes through a polymorphic " figure de resolution " ; 

 the form of these figures varies according to the particular 

 generation, and also according to particular ova. The greater 

 part of the " figure de resolution " then disappears, except a few 

 granules which serve as the starting point for the next genera- 

 tion ; that portion of the substance which disappears serves as 

 nourishment for the egg. So all the generations of the second- 

 ary and tertiary nucleoli arise "a I'aide des produits de la 

 resolution anterieure." After each "resolution" new nucleoli 

 arise, and the number of these generations is large, continuing 

 through a length of three years. The number of primary 

 nucleoli is usually from two to six ; of secondary, from 400 to 

 500 ; of tertiary, from 500 to lOOO ; the number varying in 

 different ova. Fusions of nucleoli are of normal occurrence : 

 "cette attraction des masses nucieiniens rappelle a I'esprit ce 

 qui se passe au sein de I'oeuf entre les noyaux de conjugaison." 

 In the radiation exerted by each nucleolus upon the surrounding 

 caryoplasm " nous voyons ... la confirmation d'une th^se 

 soutenue dans la ' Cytodier^se,' a savoir : que c'est sous I'influ- 

 ence du noyau que se forment les asters de division." The 

 chromatin filament does not reappear, but there is a "grand 

 nombre de generations nucieolaires et filamenteuses qui naitront 

 et disparaitront tour a tour, I'une apres I'autre, jusqu'a I'epoque 

 des globules polaires." The authors necessarily regard all the 

 previous observations on the amphibian ovum as erroneous. 

 General conclusions for all kinds of cells, based in part on 

 previous observations : there may be distinguished "nucleoles 

 plasmatiques," " nucleoles nucieiniens," and " nucleoles mixtes " 

 ("qui sont rare"). Plasmatic nucleoli consist of at least two 

 substances, " une plastine et une globuline digestible." All 

 nucleoli, "lorsque leur formation est achevee . . . representent 



