406 MONTGOMERY. [Vol. XV. 



akin to part of the substance of the nucleoli, I am unable 

 to decide. I am also unable to determine from the prepara- 

 tions at hand whether the nucleoli themselves are partially 

 composed of chromatin ; but the usual diagnostic stains for 

 chromatin do not show the presence of this substance within 

 the nucleus.^ 



To revert again to the polarity of the nucleoli. The fact 

 that the vacuoles first arise in that portion of the nucleolus 

 nearest the nuclear membrane would seem to prove that the 

 substance of these vacuoles is extranuclear in origin, or else is 

 secreted in the peripheral portion of the nucleus. But since it 

 would be obscure how the peripheral portion of the nucleus 

 should secrete a substance, and the central portion should not, 

 I incline to the former explanation, namely, that the substance 

 of the vacuoles is first produced in the cytoplasm, and then this 

 substance penetrating through the nuclear membrane, it, or a 

 part of it, arrives at that pole of the nucleolus nearest the 

 nuclear membrane, and then is taken into the nucleolus at 

 this pole. The size of the vacuoles stands in a more or less 

 direct ratio to the size of the nucleolus itself ; at the same time 

 the ground substance of the nucleolus also increases in amount, 

 though apparently not as rapidly as the amount of the vacuolar 

 fluid. 



2. Gregarine from Carinella attniilata. 

 ^ (Plate 21, Figs. 20-35.) 



{Description of the animal. — Monocystid gregarines occurring 

 in the body cavity of this nemertean. No synzigia observed. 

 Form : elongate, though not attenuate, the end in which the 

 nucleus lies being broader and terminally more obtuse than the 

 opposite end (Figs. 20 and 21). The longitudinal axis is never 

 perfectly straight, and the cuticula shows no transverse fur- 

 rows. The single nucleus is usually spherical or oval, rarely 

 lobular in outline. In the entosarc of many individuals occur 

 numerous minute, refractive granules. Neither cysts nor spores 

 having been observed, I was unable to determine the genus of 



1 However, the chromatin here might exist in the state in which it is found in 

 the growth period of ovocytes, namely, commingled with plastin. 



