PIXELL—POLYCH ATA OF THE INDIAN OCEAN 89 
Sub-genus Laosprra, Caullery and Mesnil (9), emended Pixell (41). 
23. Spirorbis papillatus, n. sp. (Plate 9, fig. 12). 
Specific characteristics: 1. Large collar setze with coarsely serrated blades and fin- 
like expansions (fig. 12¢). 2. Operculum with brood pouch, terminal cap flattened and 
surrounded with a wide phalange covered with papillee (figs. 12a and b). 8. Some set 
of second fascicle ordinary sickles (fig. 12d). 4. Some setze of third fascicle bladed 
sickles (fig. 12e). 
Locality. Chuaka, Mr Crossland’s Zanzibar collection. Numerous specimens 
“closely crowded together on the base of Sertularia colonies which are abundant in 
the sand not far below high tide level.” 
Tubes smooth, their bases overgrown with a red calcareous encrusting alga. Other 
specimens from a Pinna shell in Suakin Harbour, Red Sea, encrusted with a polyzoon. 
In both the terminal part of the tube ascends, being in some nearly erect; the 
aperture is circular and entire, about 1°5 mm. in diameter. 
Animals bright scarlet 2—3 mm. long; deep entire collar and wide thoracic 
membrane. 
The operculum varies a good deal in appearance. Fig. 12a shows a form containing 
only a few ova. The edge of the phalange is provided with long papille. In fig. 12 
these are much shorter and more irregular and the flexible side of the operculum is much 
distended with well advanced embryos which already have three or four setigerous seg- 
ments. In other specimens the papille are much smaller and sometimes only appear 
to be scattered on the upper flattened side of the phalange. 
Branchiz generally 11, sometimes only 10. They have numerous long thin pinnee 
starting some distance below the distal end, which tapers to a long thin filament. The 
operculum displacing the second gill on the left reaches about the same height as the 
functional ones. 
In the long setigerous region of the abdomen, the stomach is very evident in nearly 
all specimens owing to its dark granular walls. This is followed by eight to twenty 
setigerous segments, the geniculate setee having long deeply serrate blades. 
24. Spirorbis levis, Quatrefages (42) 1865; Claparéde (12a) 1868; Saint-Joseph 
(44) 1894. 
Specific characteristics: 1. Collar sete simple blades with coarse striations. 
2. Other thoracic seteze simple blades. 3. Ova incubated in operculum. 
Locality. A few specimens on a tube of a Sabellid from the North Harbour, Suez. 
Tube with two or three regular coils and a circular aperture: the surface is generally 
marked with three longitudinal ridges and fine scalariform markings. 
The specimens obtained complete from their tubes were young. Only two specimens 
with ova in their opercula were found. 
25. Sprrorbis cornuariatis, Phil. (40) 1844; Mérch (37) 1863; Marion and Bo- 
bretzki (85) 1875; Caullery and Mesnil (9) 1897. 
SECOND SERIES—ZOOLOGY, VOL. XVI. ‘ 12 
