TUBE OF PAKTHALIS. 171 



On the 25th of August he kindly took me on the s.s. 

 "Albatross " to the ground on which Panthalis had pre- 

 viously been found, and we were fortunate in securing 

 two promising mud masses, which, with a supply of mud 

 from the same spot, I took to the aquarium at Port Erin. 

 About noon on the following day these masses were placed 

 close against the glass sides, in different parts of a small 

 portable tank, and deposited in the aquarium building. 

 The w T ater was changed by syphoning, twice daily, to 

 correspond with the tides (this was a needless precaution, 

 but I wanted to avoid any chance of failure), but no mud 

 was in the first instance supplied, as I wished to make the 

 worms, if present, shew the position of the openings of 

 their tubes, so that I might re-arrange them if unfavourably 

 placed for observation ; or take means of guiding them, 

 if needful, in the direction of the glass. At 10.30 p.m. 

 one of the tubes displayed an opening at each end, but no 

 animal was yet visible. At 7 o'clock next morning, 

 however, at the opening away from the light, the tip of 

 the head, and two long palps were visible, but the animal 

 was exceedingly sensitive to vibration, and on my approach 

 immediately retreated. Having ascertained my "bearings " 

 I, about noon, covered the floor of the tank, round the 

 tube, with some of the fine mud brought for that purpose, 

 but restricting the depth to half an inch, in order that any 

 movement of the animal might be traced. The tank was 

 carefully watched, but no change took place during that 

 day ; on examining it next morning, however, there were 

 signs which led us to think that the worm had, during 

 the night, travelled five or six inches on the surface of the 

 mud, and returned to its starting point, whence it had 

 burrowed along the front of the tank, forming a channel 

 the whole length between the glass and the underside of 

 the old tube. The latter action was all that one could 



