22 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



supply of lobsters of the demand for lobster eggs for making 

 1 coral ' sauce. 



General. 



"Attention has been called from time to time to the 

 obstruction of the flow of sea-water through the galvanised 

 iron pipes which supply the Hatchery and Aquarium, caused 

 by the growth therein of various invertebrates. Three in- 

 teresting instances of this have occurred during the past 

 year. At the end of December, 1915, owing to a greatly 

 diminished flow of water from the upper storage tank, the 

 supply pipe was disconnected and cleaned. A few inches 

 above its junction with the pipe from the lower storage tank 

 its bore was found to be almost completely obstructed by a 

 large and vigorous colony of the tube-building Polychsete 

 worm, Salmacina dysteri. A dense mass of the tiny white 

 calcareous tubes of the worm was cut out of the pipe and 

 placed in a dish of fresh sea- water. Shortly afterwards hundreds 

 of this beautiful little worm were seen fully expanded, and it 

 was noted with interest that though they had grown in the 

 absolute darkness of the interior of the pipe they were deeply 

 tinged with the bright orange-red pigment characteristic of 

 the species. Another tube-building Polych.8ete worm which 

 has repeatedly obstructed the pipe which supplies the Aquarium 

 tanks is Sabella pavonia. In April last a large specimen of this 

 species was taken from the pipe close to the point of attachment 

 of a tap, and was placed by the Curator in one of the shallow 

 table tanks in the Aquarium, close to one side. A stone was 

 placed upon the tapering, closed end of the tube, hereafter 

 to be called the proximal end, to keep it in place. The position 

 chosen proved to be unfortunate, inasmuch as the shade 

 cast by the side of the tank made close observation somewhat 

 difficult. Accordingly, some weeks later, the stone was removed 

 and an attempt was made to remove the worm to a position 



