Gaily Marine Laboratory^ St. Andrews. 175 



Sucli forms a useful contrast witli the Inrgr; specimen, which 

 seems to have successfully eluded the agencies which, as a 

 rule, render examples of this size rare on our shores, though, 

 perhaps, abundant in tlie deeper waters. 



4. On Genetyllis citrina, a new Phyllodocid. 



This form was procured on a stone — coated with corallines, 

 a bright yellow sponge, and several ascidians — brought up 

 by a fisherman's hook in the Minch in 1865. 



The head is rounded ovate, with two black eyes of con- 

 siderable size. The four tentacles had been removed, but they 

 probably resemble those o£ G.lutea. Tlie tentacular cirri are 

 similarly arranged, viz., two shorter anteriorly and two 

 longer posterioily. Body about 3 inches in length, much 

 tapered anteriorly. Posteriorly it terminates in two caudal 

 cirri. The dorsal surface is convex, the ventral marked by 

 two elevated ridges on each side of a slightly depressed central 

 area. The entire animal is of a most brilliant chrome- 

 yellow — deepest on the middle third, which here and there 

 showed blackish-brown patches on the lamellae (cirri). It 

 tinged the water with a yellowish mucus,, and also dyed the 

 spirit in which it was immersed of the same hue. 



The dorsal region of the foot has a massive, short, bluntly 

 conical process devoid of spine or bristles, and bearing the 

 unequally cordate lamella (cirrus), which is marked by a 

 series of lines and reticulations trom a central rib» The 

 imbriccite lamellae are borne more or less horizontally along 

 the sides of the dorsum, having the central region bare. 

 The semicircular gap at the base of the lamella fits tlie 

 rounded extremity of the division to which it is attached. 

 The short setigerous region is bifid at the tip and supported 

 by a black spine, and a group of bristles shorter than in 

 G. lutea, the translucent shafts being slightly bent, and with 

 a dilated distal end which has a few spikes on each side. 

 The terminal process is finely tapered and shorter than in 

 G. lutea. The edge shows no distinct serrations, thougii the 

 adherence of particles would indicate them. Attached to the 

 ventral and posterior part of the region is an irregularly 

 renitorm ventral cirrus, vertical in position. The inferior 

 border is rounded, but the su[)erior is truncated, with a 

 tendency to a point at the upper and outer angle. The 

 cirri — both superior and interior — vary liitle in shape 

 throughout the body. 



The stone was coated with the yellowish sponge, but its 

 connection with habits of the Genetyllis is unknown. The 



