226 Dr. Johnston on the British Nereides, 



lets generally clouded in the centre with a dark undefined 

 spot. Head quadrangular ; the proboscis covered, on its lower 

 half, with fleshy papillse arranged in about twelve rows ; eyes 

 black ; antennce very short, conical. Segments very numerous, 

 the post-occipital not larger than the folio wing, bearing on each 

 side four rather short setaceous tentacular cirri, of which the 

 two anterior are shorter than the posterior pairs, and under 

 these there is a concealed rudimentary cirrus : feet all alike, 

 the superior cirrus forming an obliquely heart-shaped shortly 

 stalked leaflet, veined, entire, smooth ; the inferior cirrus is 

 similar in structure and nearly so in figure, but it is about two- 

 thirds less : between them is the proper /bo^, not very protu- 

 berant, armed with a brush of bristles disposed in a somewhat 

 semicircular manner, having a single straw-coloured spine in 

 their middle : the bristles are slender, pellucid, jointed, the 

 joint being cleft for the reception of the needle-like point : pos- 

 terior extremity terminated with two very short fleshy styles. 



This species is said to attain sometimes a size considerably 

 greater than that of the specimen just described, but on this 

 part of the coast one of 14 inches length is rare, while exam- 

 ples varying from 4 to 8 inches are not uncommon. It is li- 

 able to much difference in the tints of its colour, and the green 

 often predominates, while in young individuals the colour is 

 not diffused over the segments, but confined to their margins, 

 which are dusky, while the centre may be a pale yellow. In 

 these also the spots in the centre of the branchial leaflets are 

 usually well-marked. These are liable to be slightly affected 

 in their form by the motion and contractions of the worm ; 

 and near the tail they always incline more to the oval than the 

 heart-shape. The proboscis is either clavate or cylindrical, 

 according to its degree of protrusion. The worm tints the 

 spirits in which it is preserved with a greenish colour : the 

 body becomes blueish- or greenish-grey, and the lamellae a 

 uniform olive. 



Plate V'l. fig. 1. Phyllodoce lamelligera, of the natural size. Fig. 2. 

 The head and proboscis, as this appears when half extruded, magnified. 

 Fig. 3. The proboscis fully protruded. Fig. 4. Two segments magnified. 

 Fig. 5. A lateral view of the foot reversed. Fig. 6. The setigerous papilla 

 with its bristles and spine. 



