No. 441 .] Ci m I 'MORPHA PRNDULA A G. 



597 



carried along in all directions by a "streaming motion of the 

 plasma of the ovum." While I could not observe such a process 

 in the preserved material, the "general agreement of authors on 

 this point" (as Doflein states) makes it quite certain that this 

 phenomenon of amoeboid movement does exist. 



Miss Allen (:oo) in her observation on Tubularia crocca, says 

 that in numerous eases the outlines of the absorbed eggs could 

 be distinguished in the protoplasm of the absorbing egg. In a 

 very few favorable sections, I have been able to detect the out- 

 lines of these absorbed cells (Fig. 12, </.), but in most cases only 

 the nuclei were distinguishable. 



A great many of the primitive ova do not thus become 

 absorbed, but remain scattered among the mature eggs in 

 their original undeveloped state. Doflein suggests that possibly, 

 after the larvae have left the gonophore, these remaining germ 

 tissue cells unite to form new eggs. 



In summarizing the results obtained in this study, the fol- 

 lowing points should be noted : 



1. Corymorpha, in keeping with its usual description, is a 

 solitary form. 



2. The rhizoidal filaments of attachment are formed as 

 secretions from the papilliform processes. 



Both filaments and papillae are modifications of the same 

 structure. 



3. The central axis of the stem is filled with a mass of 

 parenchyma-like cells in which is excavated a number of longitu- 

 dinal canals. The longitudinal canals are extensions of the 

 hydranth cavity. 



4. Gland cells are highly developed in the hydranth cavity, 

 but are entirely absent from the coenosarcal canals. The 

 function of digestion thus becomes localized in one portion of 

 the enteric cavity while the coenosarcal canals function as a 

 circulatory system. A fairly well differentiated gastro-vascular 

 system thus .becomes developed. 



