REPORT ON THE ANNELIDA. 
283 
gives five and three respectively. The right lateral plate has eight teeth, being one 
more than stated by Ehlers. The mandibles are not immovably fixed to each other, 
and the dentary region has an ovoid outline interiorly, while dorsally its area is less 
than in the next form from Samboangan. The mandibular shafts are finely veined 
like sections of pitch-pine. In the much larger example, apparently of the same species, 
from Samboangan, the inner edge of each maxilla is slightly denticulated. The great 
dental plates do not diverge from the foregoing, but the left lateral paired plate (which 
is injured) appears to have only three teeth. The dentary region of the mandible is 
obliquely rhomboidal and somewhat concentrically veined, like the shell of a bivalve. 
Fig. 41.— Maxillae and mandibles of Eunice aphroditois, Pallas, from the, ventral surface ; enlarged. 
Figs. 42, 43. — Mandibles viewed respectively from the dorsal and ventral surfaces ; similarly enlarged. 
on the ventral surface (Fig. 43), but dorsally (Fig. 42) it forms a short cone, and does 
not extend so far outward as the shaft or basal region. The mandibles are fii-mly 
united. 
In the specimen from Samboangan the branchiae arise on the fifth segment as a 
small tuft, whereas in the other they are represented in the sixth segment by a simple 
filament. There are upwards of thfity divisions in the branchiae (PI. XXXVIII. fig. 17) 
in this form, whereas there are about eighteen in the example from Port Jackson, the 
pinnae in the latter being also considerably longer in proportion. It is difficult to say 
how age affects these points. 
