PHYLLODOCE LAMELLIGERA. 79 



P. groenlandica, though they form rows. The organ terminates in a firm disc with about 

 21 blackish papillae at its border. The distinction drawn between P. laminosa, with 

 less regular papillse, and P. lamelligera, with the papillae in rows, does not seem to be of 

 moment. 1 I regard them as synonymous. Gravier shows six nerves running longitudinally 

 in a section of the organ. 



The proboscis is followed by a pale, elongated, and tough membranous stomachal 

 region without papillae, after which comes the gut with its glandular walls. 



The perivisceral fluid readily coagulates in sea-water after extrusion. The cut edge 

 of a lamella also exudes a coagulable fluid, and this forms minute vermiform processes at 

 the wounds. 



This form is carnivorous, the fasces being loaded with bristles and cuticle of annelids, 

 such as the Spionidae. 



The dorsal cirri are dusky green, paler at the edges and with small pale specks. In 

 some specimens they are brownish green with a pale green margin, thus simulating 

 the condition in Phyllodoce Paretti, Aud. and Ed., which has a bright yellow border to its 

 leaflets. In a series of examples from various localities the cirri vary considerably, the 

 Neapolitan examples, perhaps, being most pointed — both dorsally and ventrally. Fine 

 examples from deep water off Montrose had them bluntly rounded in the middle of the 

 body. 



The smaller specimens are usually paler than the larger, the bluish iridescence of the 

 dorsum being only faintly marked anteriorly. The majority of those from the Channel 

 Islands are small, with a brownish body and pale green lamellae. A similar condition 

 would appear to occur at Naples. A variety also was obtained in the West Voe of 

 Scalloway, in which the dorsum was dull yellowish, with the usual central line and cross- 

 bars. The cirri were brownish olive with a dull yellow margin. Some large forms, again, 

 have more of the greenish iridescence than the blue. 



The dorsal cirrus (Plate LXVIII, fig. 1) in the anterior segments (tenth) is 

 somewhat reniform or ovate, at the thirtieth it becomes greatly enlarged superiorly so as 

 to assume an elongate ovoid form, rounded and broad inferiorly and diminishing a little 

 superiorly to a rounded tip. At the sixtieth foot (Plate LXVIII, fig. 2) the upper part 

 is wide, so that the whole process forms a broad flap. Towards the tail, the lamella 

 again becomes diminished dorsally, so that it resembles an acuminate leaf. The hypo- 

 dermic streaks and vessels trend from the margins obliquely downward and inward to a 

 central axis, and thus resemble the midrib of a leaf and its veins. A pale ridge just 

 external to the inner edge of the lamella is conspicuous in the preparations. 



In the living form these lamellae have a band of powerful cilia (visible under a lens), 

 commencing about a third from the apex of the process and coursing to the middle of the 

 pedicle at the base. The cilia are placed just behind the dorsal border of the lamella, 

 and do not follow the boldly marked curve proceeding downward and inward. The 

 lamellae are highly sensitive, shrinking with a rapid jerk when interfered with. 



Parasitic Infusoria are common on the basal portion of the lamellae. Each can 

 shorten and elongate its stalk, expand and contract its disc, which has a vestibule in the 



1 Vide Dr. Marion Newbigin, ' Millport Biol. Station Communications/ i, p. 3, 1900. 



