176 Scientific Proceedings, Royal Dublin Society. 
In a species in which so many individual variations occur, it is 
curious that the branchiz should begin so regularly on the 9th 
segment on each side, as this is one of the points most liable to 
variation in the Hunicide. Only in two specimens (one young 
and one adult) did I find the branchize beginning on the 10th 
instead of on the 9th segment on one side of the body. 
With regard to the tentacles, although not annulate as a rule, 
apparent anuulation occasionally occurs in one or other of the ten- 
tacles of the adult (cf Pl. m., fig. 2); and in two of the young 
specimens there are faint traces of annulation. It seems to me 
doubtful whether so much importance should be attached to the an- 
nulation of the tentacles, as Grube does for instance in his Revision 
of the Eunicide in the Jahresb. Schles. Gesellsch. for 1877. Ehlers 
draws attention to the variation in individuals with regard to this 
point for EL. rubrocincta." The same may be said for the dorsal 
eri (cf. fig. 7a.) 
Fam.—SERPULID&. 
(a. Serpulidee proper.) 
IV.—Serpula Philippii, Morch. (Serpula vermicularis, Phil.). 
Two specimens of this fairly-common species** occurred with 
the Lophohelia prolifera above mentioned. In both of them the 
well developed operculum is on the left side, the rudimentary on 
the right. 
A third specimen, which I think is referable to this species, 
was dredged 45 miles off Blackrock, at a depth of 275 fathoms. 
It only differs from S. vermicularis as usually described, in having 
eight instead of seven thoracic bundles of sete. Variations with 
regard to the segments between which the change of sete takes 
place do, however, occur in other members of the family (e. g. 
Sabella viola, Grube, A. f. N. Jahrg. 29. 1863, p. 58). In this 
specimen the well-developed operculum is on the right side, the 
rudimentary one on the left. 
7 Ehlers. ‘‘ Borstenwtirmer,”’ p. 345. 
18 Perhaps the best figure of the species extant is the one given in Cuvier’s ‘* Régne 
Animal.”” Annelides (Edition acc. de Planches), pl. iii. fig. 1, under the name of 8. 
contortuplicata. 
