588 



TA KU KOMM; 



the circumference of the body. The meridional canals are relatively 

 broad, broadening gradually towards their pouch-like blind extremity 

 where they may show a slight sign of branching. Each perradial 

 canal also sends forth a tentacular canal and also a pharyngeal canal 

 {ph. c) directed towards the body margin. . Aborally from the infundi- 

 bulum there proceed two excretory canals, each of which furcates into 

 two branches. In each of the two pairs thus formed of the excretory 

 branch-canal, one branch canal -'opens externally by the excretory 

 pore, the two excretory pores being situated in a diagonal relation 

 to each other, exactly as in ordinary ctenophores. 



The epidermis is very simple as compared with that cf ordinary 

 ctenophores. It appears to be entirely devoid of glandular elements. 

 The ventral body surface, which is ciliated, presents much folds, 

 especially numerously in its central parts. The oesophagus is also 

 ciliated, the ciliation here being much denser than on the ventral 

 body surface. As in ordinary ctenophores, the endoderm presents itself 

 either as a tall, vacuolated and non-ciliated or a low and ciliated 

 layer. It is of the former character along the peripheral side of 

 meridional and tentacular canals as well as along the lateral sides of 

 pharyngeal canals. The layer in these parts frequently inclose clumps 

 of the blood-corpuscles of Salpa, apparently taken up as nutri- 

 ment. In the remaining parts of the canals, the endodermal layer 

 is low and ciliated. The so-called " rosettes," usually found in the 

 endoderm of ctenophores, have not been discovered. The mesodermal 

 gelatinous tissue is traversed by some branching fibres of probably 

 muscular nature. 



In the epidermis of the ventral surface there is found a peculiar 

 kind of cells, the appearance of which has led KOROTNEFF (1888, 1891) 

 to regard it to be the egg. The cells were found in all individuals 

 examined ; they occur in especial abundance in the marginal parts of 

 ventral surface, scattered among ordinary ciliated cells of the epidermis. 

 The larger of these cells present a flask-like shape, directing the narrower 



