300 MONTGOMERY. [Vol. XV. 



la meme constitution filoide"; and similar nucleoli occur in the 

 Protista and in various cells of the Arthropoda. The " nucleole- 

 noyau " of the eggs of Cymbidia and Lithobius has a fine 

 external membrane and a convoluted chromatin filament. In 

 the amitotic division of the capsular ovarial cells of Gryllotalpa 

 the nucleolus (formed of a central portion of chromatin and a 

 peripheral layer of plastin) divides first so that each daughter- 

 nucleus receives one nucleolus. But in the amitosis of the 

 intestinal cells of Aphrophora the " nucleoles plasmatiques " do 

 not divide; and in the testicle cells (" metrocytes ") of Scolo- 

 pendra there is also a " nucleole plasmatique," and at the 

 commencement of the mitosis the "nucleole se liquefie pour 

 enrichir le caryoplasma," and is not to be found later. The 

 amitotic division of the fat cells of Geotrnpes is introduced by 

 a division of the " nucleole-noyau." 



Frenzel ('85) studied the cells of the mid-gut in insects at 

 various stages of development. Bonibyx dispar, larva : one 

 large nucleolus containing a vacuole, in which lies a small 

 spherical " Nucleollolus." Tachina, larva: here is one large 

 nucleolus, "mit kurzen zackigen Auslaufern. In seinem 

 Innern umschliesst er fast stets wenigstens einen, in der Regel 

 aber mehrere, etwa 6 bis 12, kugelige oder matt aussehende 

 Gebilde, welche nicht gerade den Eindruck von festeren 

 Korpern, sondern vielmehr von Vakuolen machen." In cylin- 

 der and gland cells of various insect larvae the nucleus is 

 filled with a homogeneous fluid, " in welche sowohl echte 

 Nukleolen, wie auch nucleolenartige Korper (' Keimflecken ' 

 oder ' Nukleolide ') einerseits und andererseits zahlreiche ver- 

 schieden angeordnete sehr klein aber stets gleich grosse 

 Kornchen eingelagert sind, die hier * Kerngranula ' oder 

 ' -granulationen ' heissen mogen." 



Leydig ('85) noticed in ganglion cells of Astaais a large, 

 spherical, granular nucleolus, in which is a large cavity ; this 

 nucleolar cavity stands in communication with that of the 

 nucleus itself. We read further : " Die Korper im Kern, die 

 man Nukleoli nennt, sind Bildungen verschiedener Art " ; some 

 arise out of the nodal points of the nuclear network, others out 

 of the " Kernplasma." 



