igii.] J. Stephenson : Some Aquatic Oligochaeia. 213, 



In December of last year (1910), I received, through the 

 kindness of Dr. Annandale, a tube containing specimens of this 

 worm, sent off ahve from Calcutta. On their arrival in Lahore, 

 about half the specimens were dead and disintegrating ; a number 

 were alive but motionless; and a few were still active, protruding 

 themselves from their tubes. A subsequent consignment received 

 in Januar}' of this year were unfortunately all dead. 



Observations on the tubes, and on the mode of progression 

 of the animal, confirmed Annandale 's statements. The tubes 

 were composed of bits of leaves, small fragments of wood, and 

 black granular matter ; the}^ were always found floating on the 

 surface. In the second batch of specimens the animals were 

 all dead, as has been said, and the tubes were empty ; here 

 in all cases there was seen to be a thin and delicate transparent 

 tube within the rough outer one ; this was probably the case, 

 though it was not observed, in the first batch also. 



The mechanism of progression was much the same as noted 

 by Annandale, modified by the fact that the tubes were floating 

 on the surface. Thus, in a watch-glass, the animal protruded 

 the anterior part of its body downwards and forwards till it 

 touched the bottom, where it attached itself by means of its 

 circular pharynx, using this latter as a sucker ; it might then 

 crawl slowly along, the tube still floating on the surface, without 

 ever letting go its hold. Or it would contract its body, thus 

 pulling the tube forward ; then it would let go, and extending 

 itself regain its hold on the substratum by means of its pharynx 

 a little in advance of the former place. 



The most distinctive characters of the species are to be 

 found in the setae, gills and palps. These features have however 

 been previously described : and I will therefore only add a few 

 particulars concerning the internal anatomy, observed during the 

 examination of the living worms. 



The pharynx is large and wide, and extends backwards to 

 dissepiment |; the oesophagus, which succeeds, reaches as far 

 as } ; chloragogen cells begin in segment vi ; the stomach occupies 

 ix ; the alimentary tract narrows again in x, to dilate finally 

 in xi, where it becomes the intestine. 



Body-cavity corpuscles are present, as small circular or irregular 

 homogeneous and refractile bodies. 



The blood is a very pale red. The dorsal vessel is dorsal 

 only in name throughout most of its length, as in related forms ; 

 it appears as a clear streak in the chloragogen covering of the 

 intestine and stomach, being thus embedded in the alimentary 

 wall; in segment ix it becomes lateral in position, having thus 

 far been ventral ; in viii it separates itself as a distinct vessel 

 with walls of its own ; arid shortly after this takes up a dorsal 

 position above the oesophagus. The ventral vessel is distinct 

 from the alimentary canal throughout the body. Contractile loops 

 are present in the hinder part of segments vii and viii respectively,, 

 lying on the septum. 



