ITS YELLOW DYE. 178 



isliing to tlie middle of the body. On the outer side 

 of each tuft is a small tentacle, or rather a fleshy 

 tubular sheath, fi'om which issues at will a flat pencil 

 of fine bristles, arranged transversely to the line of 

 the animal : they point upwards and slightly outwards. 

 The bristles are very fine and gradually tapering to a 

 point ; they are plain, except near the tip, where they 

 are clothed with the most delicate barbules, which 

 however are closely appressed. These pencils of bris- 

 tles do not cease with the branchial tufts, but are 

 continued on every great annulus to the head. The 

 mouth is constantly being everted and retracted ; in 

 the former process a trumpet-shaped mouth is unfold- 

 ed, the edges and interior of which are set with dense 

 papillae ; sometimes, especially after a day's captivity, 

 this mouth is evolved to a still greater extent, so as to 

 project the interior itself in a convex or almost globu- 

 lar form, which assumes a pellucid appearance, and a 

 pale-brown hue. The rings of the body are occasion- 

 ally adorned with a blue iridescence ; they are longitu- 

 dinally wrinkled, and hence there is a sort of reticulation 

 on the animal. When I first touched it, it discharged 

 (I think from the tufts) a yellow fluid, which strongly 

 stained my fingers : and on being kept in a saucer of 

 clean sea- water, I found the latter in 24 hours tinged 

 with olive ; as was the water, with which I replaced it, 

 the following day. 



I subsequently found another specimen of this 

 animal in similar circumstances. The colouring fluid 

 was poured out in tliis case much more profusely. I 

 stained some writing paper with it ; the tint was at 

 first a full greenish-yellow, but after a day or two it 



