344 FILOGRANA IMPLEXA. 
the bottom. One of the latter showed three segments behind the head, and in all the two 
eyes were distinct. 
The masses of tubes (Plate CX.XI, fig. 8) formed by this species are often of large size— 
nearly a foot square—showing that by rapid budding it can hold its own in the struggle 
for existence—probably quite as effectually as in the case of those with numerous ova, these 
being few. The notion that the character of the tubes as to closeness and divarication may 
indicate specific distinction is uncertain. Much will depend on freedom from injury in the 
living or dead condition and the site inhabited. 
In considering the relationships of the various races of Filograna little can be added 
to what has been published lately.! 
No form in the whole range of the Polychets is of greater interest than this species, 
the life-history and reproduction of which, its plastic and protean character, as well as the 
concrete calcareous masses, often of considerable size, formed by its thread-like tubes, 
combine to surround it with a halo of interest were it only for the study of variability in 
a single type. Moreover, in genial waters it flourishes with a profusion which sometimes 
causes considerable inconvenience ; thus Mr. Chadwick, at the Port Erin Biological Station, 
found that the flow in a supply-pipe from a tank was gradually diminishing, and on investiga- 
tion a vigorous mass of Filograna was found blocking the lumen. 
Seba? (1758), in alluding to various marine “ mosses, corallines,”’ and tubular corallines, 
which he figures, specially refers to this species, which he found adherent to rocks and various 
structures, in one instance forming the basis (fig. 19a) to which Thuiaria thuja was attached. 
In the “ Thesaurus” he gives a figure in which the spaces between the fascicles of tubes 
are correctly represented. 
Nothing definite appears in the remarks of Plancus’ “‘ De conchis minus notis” bearing 
clearly on this form, though he is quoted by some authors. 
Berkeley® (1827) described the form with the opercula which he dredged at Weymouth. 
The same author in the ‘Zool. Journ.’ gives a figure (Plate XVIII, fig. 3) which is in the 
volume of supplementary plates (and not in vol. i), showing a somewhat pointed hollow 
operculum on each dorsal filament, seven pairs of thoracic bristles, and in the posterior 
region indication of a twist, or it may be a bud. 
Oscar Schmidt* (1848) alludes to Felograna implexa and states that he has found a new 
species at Farée—with buds at all stages—such, however, being only a phase in the common 
form. 
Salmacina, Claparéde states (1868), is distinguished from Protula by the large bristles 
of the first segment—a character in which it approaches the Serpulids and Filograna. The 
absence of an operculum, however, separates it from both. 
There is nothing in the structure of Filograna Huzleyr, Ehlers, from the Tortugas, to 
indicate other than a variety of a species with world-wide distribution. The bristles and the 
tips of the branchize fall into line when compared with those of Salmacina inerustans and 
S. aedafrcatriz. 
1 «Studies on Filograna,” ‘ Ann. Nat. Hist.,’ ser. 9, vol. iii, January, 1919, p. 125. 
* Catalogue of the curiosities in the cabinet of Albertus Seba. 
8 9 
P]. xviii, fig. 8, absent from the University copy of the ‘ Zoological Journal.’ 
4 «Prorieps Notizen,’ No. 143, p. 162, August. 
