19 1 7- CoLGAN — Pectinaria Koreni from Dublin Bay. 137 



gives as slightly curved, were in my specimens quite straight, 

 and the paleolae or golden bristles which crown the head 

 and suggested to Miiller the appropriate name auricoma 

 for the best known species of what is now the genus Pectin- 

 aria, numbered in my specimens 17 and 13, respectively, 

 and not about 14 as given by Malmgren. This character 

 is apparently variable. 



Twenty- four hours after the taking of the smaller specimen 

 it was transferred from sea water to fresh water in the 

 belief that it would thus be quickly killed so as to admit 

 of fuller examination. The animal, however, appeared to 

 be little affected by immersion in fresh water. Its gills, 

 once blood-red, turned quite pale, and several of the upper 

 body segments emerged from the tube, but the tentacles 

 continued in active motion. After half an hour's immersion 

 the animal, still in its tube and still quite Hvely, was returned 

 to sea water. Within ten minutes the gills had resumed 

 their blood-red hue, and within half an hour the worm 

 had completely abandoned its tube. 



While examining the setae under a quarter-inch objective 

 I observed a stream of minute, cream-coloured eggs issuing 

 from the body slightly below the gills at a point where 

 no rupture of the tissues was perceptible, and similar eggs 

 could be discerned within the body in several of the trans- 

 parent parapodia or bristle-bearing feet. This egg- 

 deposition continued for about four hours until fully a 

 thousand eggs lay in the bottom of the watch glass in which 

 the worm, which survived until the following day, was 

 kept under observation. Development of the eggs was 

 well advanced and their form, as one occasionally presented 

 its edge to the observer, was seen to be discoid with a 

 central depression and not globular as they appeared to be 

 when viewed in face. After two days further development 

 disintegration of the eggs set in and my hopes of rearing 

 a brood of young Pectinarias were dashed. No doubt the 

 half-hour's immersion in fresh water had brought about 

 a premature deposition of the eggs. I am not aware of 

 what is the normal method of reproduction in this section 

 of the marine annehds, whether the eggs are laid singly 

 or in cocoons or capsules or in gelatinous masses as occurs 



