164 Prof. M‘Intosh’s Notes from the 
No modern investigator, however, would feel safe in 
relying on these distinctions without also subjecting the 
bristles, hooks, body-wall, and life-history to careful exa- 
mination, In order to indicate the proportional abundance 
of the Serpulids in British waters, notes of a few of the 
collections made by exploring ships and by zoologists at 
various limited localities are added, as well as extracts 
from one or two memoirs devoted to the group. 
Philippi* (1844) furnished a description of the Medi- 
terranean Serpulids, entering no less than twenty-six, though 
Grube in the same region had only twelve. Philippi relied 
much on the structure of the opercula and, in the case of 
Portula, on the spiral arrangement of the branchiz, or the 
fan-like nature of the branchize in Psygmobranchus. These 
data are insufficient, and consequently considerable con- 
fusion resulted. Thus, for instance, his genus Vermuilia 
included six new species, and of the two new forms one was 
the common Pomatoceros triqueter and the other was pro- 
bably synonymous with the ubiquitous Serpula vermicularis, 
entered, as also was the former, under another genus. 
Morch f (1861-63), in his “ Revisio Critica Serpu- 
lidarum,” has about 125 species of Serpulids under six- 
teen genera, Spirorbis having no less than twenty-seven, 
Hydroides seventeen, Serpula fourteen, Vermilia twelve, 
Protula and Placostegus each eleven, Ditrypa eight, and 
the others smaller numbers. This list could be considerably 
reduced almost under every genus. 
Dr. Johnston f (1865) gives ten in the body of the work, 
and in the Appendix Dr. Baird adds another and no less 
than seventeen species of Sprrorbis from the literature of 
the subject ; but in both cases the number of species needs 
substantial reduction, since some appear under two or three 
titles. 
De Quatrefages § (1865) mentions about a hundred and 
nine species as occurring throughout the ocean; but it is 
evident that many are synonymous, and that the series 
could be much reduced. 
Twenty species are recorded by Malmgren || from the 
extensive northern waters, ranging from Greenland to the 
North Sea; but some of these are evidently doubtful, such 
as the second species of Filograna and several species of 
* Archiv f. Naturges. Bd. x. p. 186, Taf. vi. figs. A-T. 
+ Naturhist. Tids. Kj¢benhavn, Bd. i. p. 347. 
t Cat. Worms Brit. Mus. pp. 264 & 346. 
§ Annel. t. ji. pp. 484 &e. 
|| Annul. Polych. (sep. copy), p. 119. 
