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J. F. Mi HOT T. 



are approximated but when extended they are separated by wide 

 interstices so that the general color of the animal becomes much paler, 

 approaching transparent. About the periphery are thickly scattered 

 dull yellow or whitish cells, sometimes forming a rather prominent 

 border. 



The most prominent feature of the animal is the two long chalky 

 white tentacles which lie in great writhing snake-like masses on 

 either side of the sense organ, usually visible from the outside. These 

 are very long and very contractile, quite similar to those described for 

 Ctenoplana. The secondary branches are covered with batteries of 

 nettle cells. Except when floating as described above, they are usually 

 retracted in the sheaths, occasionally with I he tip projecting like a 

 tongue. At other limes, however when the creature is more animated, 

 it throws out the whole tentacle in a cloud of white filaments, while 

 crawling. And to watch it at such a time, shooting out and retracting 

 the tentacles, moving along the side of the aquarium like a battle-ship in 

 action, is truly a remarkable spectacle. 



Touching with a needle will also frequently cause it to throw out 

 the tentacles, (fig. 3). 



The sheath is raised in a log-like ridge along the dorsal surface» 

 ending freely a trifle back of a notch in the periphery. The mouth of 

 the sheath is separated from the body to form a short retractable tube. 



Next to the tentacles the most prominent thing to be observed is 

 the network of anastomosing digestive canals, which ramify throughout 

 the body (fig. 2). The creature's habit of constantly twisting itself out of 

 shape makes it extremely difficult to plot with any certainty the course of 

 the canals. There are three or four long channels that run more or less 

 parallel to the axis of the tentacles and send out branches peripherally. 

 At a point about half-way to the edge these branch much more profusely. 

 The inner portion thus appears paler and clearer when viewed from 

 above. There is no peripheral canal. The canals end blindly in finger- 

 like processes. I have not been able to make out with certainty any 



