LAGIS KORENI 



57 



or smaller end above the surface, and often escaping to the surface of the sand through 

 fissures caused by the digging of the annelid. The French author also noticed that the 

 current could be reversed at will. The object of this current was supposed to be mainly 

 for the purpose of ejecting the sand passed through the alimentary canal. Arnold Watson, 

 however, found that constant additions are made to the broad end of the tube, and space 



A.T. W. 



Fig. 14>l.—-Lagis Koreni at work amongst sand. A current with sand and other particles is 

 issuing from the tube in the rear. (After Arnold Watson.) 



for this work is obtained by suction. After the sand has been traversed by the combs 

 (palea3) of the annelid, and the particles brought within reach of the tentacles, that not 

 swallowed is carried away by a strong upward current caused by the peristaltic action 

 above mentioned, passing between the wall of the tube and the dorsal surface of the 



Fio. 142. — Papillose building-organs, bo. (cement- gland) of Lagis Kor> 



(After Arnold Watson.) 



annelid, and is ejected through the upper or smaller end, this forming the mounds usually 

 observed on the surface of the sand (Fig. 141). In connection with the chamber thus 

 formed at the broad end there is often a downcast shaft a short distance from the tube. 

 Such currents are not the result of peristaltic action, but are due to two currents through 

 the tube at opposite sides of the annelid, caused by the action of the body (Watson). 

 This persevering observer also noticed the parts employed in the building of the tube, 

 viz., a pair of dorsal "downwardly directed lobes" (Fig. 142) acting in connection with 

 a lower lip just in front of (" above ") the first ventral shield. Associated with these 

 is a cement-gland, which, when the sand grain — carried by the papillae to the building 



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