80 PHYLLODOCE LAMELLIGERA. 



centre and a band of cilia around its edge. Free forms — -of the greenish hue of the 

 borders of the cirri — become entangled in the mucus surrounding the annelid. 



The ventral division of the foot consists of a somewhat clavate process with a bifid 

 tip, from which the spine issues, and beyond which the lamellge project considerably. 

 The bristles (Plate LXXVIII, fig. 6) have pale shafts slightly curved towards their 

 dilated extremities, which have a series of minute spines, forming a hispid margin on 

 each side of the peak in some, and they are not confined to the edge only, but pass 

 some distance downward on the obliquely striated bulbous region. In certain views 

 the spines, which are slightly curved, appear to increase in size from the lower part of 

 the dilated region to its apex. This explains the appearances frequently observed at the 

 tip. The tapering terminal blade has its edge boldly serrated, and is of moderate length. 

 The serrated edge, is split inferiorly, and each limb is spinous. Considerable variation 

 occurs in the length of the spines, which are very long in small examples from Naples. 

 The inferior cirrus is almost reniform in front (tenth), but becomes ovate-acuminate as 

 the fiftieth foot is approached, and continues of this shape to the posterior end. It is 

 fixed to the posterior and ventral border of the inferior division for fully a third of its 

 length and is borne vertically. The variations in the feet may be estimated by comparing 

 fig. 2, Plate LXVIII, with fig. 3, from Naples. 



Reproduction. — Some deposited green ova in a gelatinous mass in May. The animal 

 readily secretes a large quantity of mucus and in this the eggs very probably are 

 immersed. A ripe male, which is distinguished by the paler-yellowish hue of the body and 

 the bases of the feet — caused by the masses of white sperms — occurred in June (19th). 

 The sperms have a comparatively large head and long slender tail. Ehlers observes that 

 the female is larger than the male, and Dalyell mentions that young specimens are 

 usually green, but it is doubtful if he had always the same type before him. 



A recently developed tail is quite pale, and is thus in contrast with the fine blue 

 segments in front. The dorsum of the pale region has a median row of dark specks, 

 whilst a less distinct speck occurs at the base of each lamella. 1 



When immersed in clean sea- water the animal is for some time very restless, moving 

 its elongated and complex body with ease and grace, first in one direction and then in 

 another. The lamellge (cirri) reverse their feather-like motions in whole or in part as 

 occasion requires, and apparently act in conjunction with the bristles, and thus the most 

 varied movements are performed as easily by this animal with its feet in hundreds as by 

 one with a few. After it secures a suitable position, no motion of any organ is noticed 

 for considerable periods, the cilia on the lamella? sufficing for aeration. In this condition 

 the lamellae are stretched outwards from the body, except at the curves, or when com- 

 pressed against the glass ; while the tentacular cirri are laid straight backwards. By the 

 aid of gelatinous mucus secreted in considerable quantity, it can also swim near the 

 surface of the water, and appears generally to relish the gentle movement of the 

 lamella?. A regular series of wave-like contractions pass from before backward — 

 about five or six per minute — in some otherwise at rest. 



1 Vide A. Michel, " Recherches sur les Regenerations chez les Annel.," f Bull. Sc. Fr. et Belg./ 

 31, ser. 4, 1893, pp. 245—417, pis. 13—19. 



