10 
THE VOYAGE OF FI.M.S. CHALLENGER. 
and rightly gave his figure four eyes ; and Dr. Baird ^ likewise observed the true 
condition in several species. 
When closed, the mouth presents a simple puckered orifice with two prominent fleshy 
lobes running to the anterior border of the head, and which are probably the homologues 
of the same parts in Euphrosyne. They are not merged into the gape during the 
extrusion of the proboscis, but form two sides of a special triangular fold superiorly. The 
posterior border of the mouth occurs at the margin of the fourth segment. The 
extruded proboscis probably agrees with that of the Mediterranean form in being in 
three tiers, viz., a membranous basal portion, a denser median, and a firm cartilaginous 
distal part in the form of two lateral lips. 
Each of the typical segments of the body bears a branchial tuft, a well-marked dorsal 
papilla with a fascicle of bristles, and immediately behind a long madder-brown cirrus 
upon a pale basal portion, while the ventral division has a very long tuft of bristles, 
and a shorter pale cirrus placed inferiorly and posteriorly. The first three body-segments 
possess no branchial tuft,' but, as mentioned by Pallas, have a second small pale cirrus 
at the base of the dorsal one. 
The dorsal bristles spring’ in a radiating fan-like manner from the papilla, and 
consist of long tapering organs with yellow tips and a secondary spur at the base 
(PI. Ia. fig. 7, which represents one from the middle of the dorsum). The distal end is 
pointed — smooth on the side with the basal spur (absent in Dr. Baird’s Cliloeia tumida from 
India), but on the opposite edge furnished with from twelve to twenty large recurved fangs, 
besides having the tip beyond the latter slightly serrated. Kinberg’s artist does not 
clearly define the spur.^ In the preparations the yellow pigment is most intense just 
above the latter, and this colour is very characteristic in glancing at the bristles en masse 
in spirit-preparations, especially when contrasted with Notopygos and allied forms. 
These bristles have a slight curve, and terminate inferiorly in a slender and almost 
pointed extremity, so that they are fusiform. The anterior dorsal bristles differ in having 
in some cases smooth tips and a longer basal spur (PI. Ia. fig. 8), while in others there 
are very few recurved fangs. The mere number of the latter is therefore immaterial. 
The bristle-papilla to which the dorsal fascicle is attached is peculiar in rising out of 
a kind of pit in the adjoining skin, which forms a free margin all round, with the 
exception of the posterior third. The whole tuft can thus be readily moved. 
The ventral bristles consist of long yellowish structures having tips like that repre- 
sented in PI. Ia. fig. 9. They terminate inferiorly in long tapering roots, which 
appear to be solid for a considerable distance. There is little difference between the anterior 
and posterior forms, except that the former are more slender. It will thus be apparent 
that all the bristles of this form are modifications of a single type. 
The dorsal cirrus is a simple subulate process springing from the bristle-paj^illa 
^ Journ. Linn. Soc. Land., vol. x. p. 230. ^ Qp p]_ xi. fig. 1, G. 
