322 



A NEW ASTOMATOUS CI LI ATE. 



represents an irregular three-dimensional reticulum of the chromatin 

 substance. Small as it still is, the meganucleus occupies a large part of the 



apposed to, the meganuclear threads. In this respect, one is reminded of 

 Metcalf's illustration, especially his fig. N, of the excretory vacuoles of 

 Opalina. As was stated by that author for Opalina, the vacuoles lack, in 

 contrast to those described before of full-grown individuals, a definite limiting 

 wall and seem in their nature to be nothing more than enlarged areolar spaces 

 of the entoplasmic foam. In my opinion, the same may be said of the spaces 

 which are occupied by the non-plasmic spherules before alluded to. In the 

 developmental stage under consideration the same spherules are found more 

 numerously and in a considerably larger size than in the earlier stage 

 before descreibed, plainly indicating that they are something that grows, 

 not only in number, but also in bulk as the organism advances in development. 

 They lie rather closely crowded in the central parts of the body, partly 

 inclosed in the mesh-like spaces or hollows of the yet spongy-like mega- 

 nucleus (fig. 6.). I have not been able to trace subsequent changes of the 

 non-plasmic spherules, but am of the opinion that they, at a certain stage of 

 the development of the organism, begin to fuse together, finally to form a 

 single mass, and that this, as the substance increases in volume, distend 

 from within the growing meganucleus ; so that, while it occupies that 



body. Its general appear- 

 ance reminds one of .the 

 same organella in Opali- 

 nopsis scpiolac studied by 

 DoBELL. n The excretory 

 vacules are now extensively 

 and very distinctly deve- 



Fig. 6. 



Two longitudinal s étions of a you 



ng individual. Xg8o. 



loped, a number of relatively 

 large ones existing in close 

 connection with, or directly 



i) Dobf.LL, CC. — Some observations on the Infusoria parasitic in Cephalopoda. Quart. Journ. 

 Microscop. Sci., Vol. 53, 1909. 



