REPOET ON THE ANNELIDA. 
517 
disk are fewer, and the conical apices are longer and more acute. Thus, for instance, a 
British example of Serpula vermiciilaris has forty-six complete radii, one or two having 
double apices ; whereas in the form from Kerguelen there are thirty -five radii, one 
having the apex double. 
The anterior bristles, which occupy seven pairs of setigerous processes, are stronger 
and larger than in Serpula vermicularis, with the tip very finely tapered (PI. XXXIa. 
fig. 23). The wing is comparatively narrow. The usual shorter and more slender 
series occur in each tuft. 
The hook shown in the previous publication (Transit of Venus Exped., Phil. Trans., 
vol. 168, pi. XV. fig. 16) is less broadly triangular than usual. 
The food of those from Station 151 (off Heard Island) consisted of Diatom ooze, a 
considerable number of sponge- spicules and Eadiolarians, however, being present 
amongst the Diatoms. Those from Marion Island (Station 144a) had likewise Diatom 
ooze containing difierent forms of Diatoms, a few minute Foraminifera, Eadiolarians, and 
sponge-spicules. 
The tubes of those from Marion Island present many prominent rings from the 
widely expanded apertures, showing that growth had apparently taken place to some 
extent by fits and starts, or at least that periods of quiescence had occurred. This 
condition has been descanted on by Claparede^ in the case of Delle Chiaje’s Serpula 
crater from the Bay of Naples. The tube is much longer and more slender than in 
Serpula vermicularis, and instead of the recumbent and attached condition of the 
latter it forms free masses, to which are fixed various organisms, e.g., Polyzoa. When 
the masses are uninjured it is found that the tubes are slender inferiorly, and that they 
dilate gradually toward the anterior end. In the interstices of one mass of tubes is a 
tunnel of Neottis antarctica; while Compound Ascidians, Polyzoa, and other structures 
show by their condition that the tubes are comparatively free. Many of the tubes are 
soldered together longitudinally. None are straight ; all are more or less sinuous^ 
In transverse section, toward the termination of the anterior third, the hypoderm 
and its basement- tissue are thicker ventrally than in Serpula vermicularis. The 
longitudinal dorsal muscles are also more extended, and are connate in the median 
line. The longitudinal ventral muscles are proportionally smaller, but the nerves and 
neural canals have the same relative position, that is, the latter lie near the muscles. 
In both a line of longitudinal muscular fibres passes between the nerve-cords. The 
fasciculi of the great longitudinal muscles are pennate in transverse section. The 
changes which ensue in the appearances of the body-wall of the Serpulidse in full 
maturity are well shown in a transverse section of Serpula uncinata, Grube, given by 
Prof. Schenk ^ in his paper on the development of the eggs in the group. The present 
species appears to be the Serpula narconensis of Dr. Baird, one example of which, 
* Annel. Ch^top. (Supplement), p. 160. ^ Sitzungsb. d. k. k. Akid. d. Wiss. Wien, Bd. Ixx., 1874. 
