EULALIA VIRIDIS. 59 



greenish inferiorly, whereas the ripe males are whitish on the ventral surface — from the 

 masses of sperms. The latter have a globular head and a long tail like those of Nereis or 

 Lepidonotus, and are much larger, for instance, than those of Girratulus tentaculatus. 



Lo Bianco 1 gives November as the month in which the sexual products are present 

 in the Neapolitan examples. 



Louis Fage 2 has recently described the segmental organs of this form, the nephridia 

 rarely having more than three divisions, fan-like in outline, the border being formed 

 of the solenocytes from which small tubes lead to the duct, whilst the " pavilion " or 

 genital duct is funnel-shaped and leads to the exterior, becoming specially enlarged at 

 the epoch of reproduction, and transmitting the sexual products, as in other members 

 of the family. 



Habits. — In the groups of adults procured in the fissures of the shelving rocks, 

 amidst muddy debris, only occasionally are a few small forms, about If in. long, pro- 

 cured. In confinement they remain at the side of the vessel, while rapid undulatory 

 motions take place from head to tail, probably in connection with respiration. No 

 ciliated band, however, was observed on the lamellae. They also seek shelter under 

 Ascidians and sponges, and if prevented, sometimes coil themselves into a rounded knotted 

 mass. Some take shelter both in the sea and in confinement in tubes of Serpula and 

 Sabellaria, to which they cling with tenacity. The movements of this species have been 

 recently described by Gr. Bolm 3 as largely due to what he terms " thigmotactisme." 

 Bright light causes disordered movements. 



They tinge the spirit at first of a pink colour, and become themselves of various 

 shades of straw colour or pale brown. 



They are chiefly littoral, but occasionally come from deeper water. 



0. F. Miiller's description (1771) of this, as of other Annelids, is remarkable for its 

 general accuracy, and the same may be said of his figures in the " Nat. einiger Wurm- 

 Arten." 



Audouin and Milne- Edwards (1834) described a Phyllodoce Gervitteii, which only 

 differs from their P. clavigera in the absence of the median tentacle and the brevity of the 

 tentacular cirri. It is possible that this absence may have been accidental, as no other 

 species so closely approaches it. De Quatrefages followed, so that he represented this 

 form by three species. 



The Eulalia virens of Ehlers (1864), from the Adriatic, comes so close to this species 

 that it is doubtful if it can be separated. 



It is difficult to identify the Phyllodoce ellipsis of Dalyell, or the P. Griffdhsii and 

 P. cordifolia mentioned by Johnston in the Catalogue of the Annelids in the British 

 Museum (1865). Grube thought P. Griffithsii resembled his Eulalia punctata from St. 

 Vaast la Hougue. 



This species seems to be subject to considerable variation in colour, for so far as 

 can be observed, the E. ornata of De St. Joseph (1888) differs only in this feature. At 

 any rate, those examples forwarded from Plymouth by Dr. Allen did not show sufficient 

 1 'Mitth. Zool. Stat. Neapel/ xiii, p. 486 (1899). 



3 'Ann. Sc. Nat./ 9 e ser., iii, p. 274, figs. 1, 2, and 3 ; pi. vi, fig. 1-3. 

 3 'Ann. Sc. Nat./ 9 e ser., iii, p. 67, 1906. 



