78 PERCY SLADEN TRUST EXPEDITION 
the operculum has 24 teeth round its edge. The secondary operculum is in both cases 
quite small and rudimentary. 
The specimen from the bottom of SS. Juba is smaller than the other two and has 
its functional operculum (with eight spines) on the right ; the smaller one on the left is 
also almost fully developed and shows the same number of spines. 
Another operculum with eight central spines was found with some material from 
Dongonab, but no trace of the rest of the animal could be found. 
The uncini have six or seven teeth, in this being intermediate between Willey’s and 
Marenzeller’s specimens ; otherwise the uncini and setee agree very closely with those 
figured by the latter author. 
This species is interesting in having a wide distribution considering its apparent 
rarity. The species was established by Marenzeller in 1884 on one specimen from the 
east coast of Eno-sima Island (S. Japan). Willey (50) records another single specimen 
without a tube from the Gulf of Manaar in 11 fathoms in 1905. 
8. Hupomatus spinosus, n. sp. (Plate 8, fig. 5). 
Specific characteristics: opercular lower funnel with about 32 long pointed teeth, 
the upper or central one with 10 strong tall spines, each with distinct terminal hook 
pointing outwards and a nearly terminal inner one pointing downwards and inwards and 
also an inner median one near the base. The eleventh spine is much longer and curved 
over these and has only a basal hook (fig. 5). 
Locality. Five specimens from Suez. 
The tubes are thick with longitudinal ridges and somewhat irregular growth lines— 
one has sand grains adhering to it. The length of the thorax and abdomen combined 
varies from 10—23mm. with a maximum width of 3mm. 
The branchize, of which there are about 11 pairs, have rather short terminal filaments 
and pinnze. The pedicle, which is generally rather longer than the gills, is 3mm. in one 
of the larger specimens. The spines of the operculum are almost black and are much less 
raised than in HL. exaltatus. There are also dark brown bands anterior to the tori, these 
being especially marked in the thorax, giving a very distinctive appearance. 
The collar is entire and not very high nor ample, the ventral lobe thus forming a 
straight band. The collar fascicle consists of large bayonet sete together with some very 
fine capillary ones. The thoracic uncini have seven teeth, the abdominal six; both these 
and the setze have the usual shape. The abdomen consists of about 100 segments in the 
large specimens. 
Genus Pomatostecus (Schmarda). 
Generic characteristics: 1. Several horny disc-like opercula united by a central 
vertical column. Pedicle with broad lateral wings. 2. Collar sete bayonet-shaped 
and covered with fine hair-like processes, generally with simple bladed forms also. 
3. Abdominal setze sickle-shaped (setee of Salmacina). Ehlers (15, p. 299) considers 
this point of special importance in distinguishing Pomatostegus from Spirobranchus. 
