788 MISS HELKX riXELL ON 



ridges bearing the tori being espi^oially deep in colour. Ab- 

 domen pinkish ; there is a short anterior asetigerous region, and 

 posteriorly nearly covering the last centimetre or so of dorsal 

 surface is a chalky white strap-shaped raised glandular area. This 

 is the terminal dorsiil gland mentioned by 8t. -Joseph (24) as 

 possibly serving in the construction of the tube. It tapers 

 anteriorly and ends abruptly posteriorly just above the vertical 

 slit-like anus.* Along nearly the whole of this glandular region 

 the ordinary abdominal set:e are replaced by fascicles of about li\e 

 slender cajiilliary seta^ without blades and nearly equal in length 

 to the width of the abdomen at this place. The collar is entire 

 ventrally and has a deep incision on each side — the lateral lobes 

 being continuous with the wide thoracic membrane. 



The functional operculum is large and transparent and carried 

 by the second branchia fi-om the dorsal side. The pedicle is 

 generally coiled twice like the other gills ; except in very young 

 .specimens there is a small club-shaped one terminating the 

 branchia on the opposite side. 



All the coUai" seta^ and most of the other thoracic set:« have 

 ^simple narrow blades ; amongst them in the posterior thoracic 

 fascicles ai-e to be found a few of the typical bladed sickles 

 (fig. 4:c). The abdominal seta^ are more or less sickle-shaped, 

 though they easily become folded (figs. 4 d, e) or straightened 

 out. 



Several of the s})ecimens examined were much smaller and 

 obviously young forms, with 70, 83. 101, 11 -i abdominal segments 

 ;\nil fewer branchiae than in adult specimens. 



Genus Protula Risso (23), 1826. 



Cieneiic chai-acteristics :- — - 



1 . No operculum. 



2. Collar setiB simple tapered blades (fig. 5h). 



3. Terminal dorsal gland present. 



5. Protul.\ PACiFicA, sp. n. (PI. LXXXVII. figs. 5 a-5f.) 

 Specific characteristics : — 



1. Ventral lobe of collar notched. 



2. Abdominal setje somewhat sickle-shaped in the anterior 



region, narroAV terminal bladed ones posteriorly, 

 o. Uncinigerous tori extend from segment 3 to the end of the 

 abdomen. 



4. Uncini with numerous small teeth, the posterior one long 



with a bulbous extremity (fig. 5f). 



5. Thoracic seta^ simple blades with sometimes a few seti>3 of 



Apomatiis posteriorly. 



* In section the gland is seen to consist of epitlielial cells crowded with spherical 

 irranules which stain easily with iron luvmatoxylin but not with Delatield's. The 

 iiland is apparently unchanged by the presence of acid in the preservatives and 

 therefore does not appear to be calcareous. i 



