POLYCH.«TA— BENHAM. 83 



consist of extremely line grains of grey sand, looking like mud grains. Such tubes 

 have thicker walls than those with coarser grains ; and it is such a tube that Ehlers 

 describes. In both kinds I find ech'nid spines, and sponge spicules so embedded as to 

 produce a smooth external surface. 



One such tube measures 90 mm. long, with a diameter of 15 mm. at its upper 

 end, and its wall is 3 mm. in thickness. 



Most of the worms measure from 50-70 nun., with an anterior width of 7 mm. 

 some are larger than this, and one is 90 mm. long. Gravier, however, gives 100 mm. 

 as the length of a specimen Avith 86 segments. 



The number of notopodial bundles varies from 40, 43, 45 and 49 in those 

 examined. Gravier gives 54 and Ehlers 48. 



The number of ventral gland shields is 14, 15 and 16, in niy specimens. Gravier 

 found 14. 



There is no need to add anything to Gravier's account. 



Localities. — ■ 



Boat Harbour — Among rhizoids of floating brown Alga^ (Dr. McLean). 

 Boat Harbour, 2-4 fathoms. Station B, 25 fathoms. 



Commonwealth Bay — 



Station C, 15-20 fathoms. 

 Station D, 45-50 fathoms. 

 Station E, 55-60 fathoms. 



Distribution. — South American Antarctic (Gravier), Kai:^er Wilhelmll Land (Ehlers). 



Terebella vayssieri Gravier. 



Phyzelia vayssieri Gravier (1911), p. 130, pi. X, figs. 121-123; pi. XL figs 

 134, 135. 



The tube of this species, of which several were gathered, consists of variously 

 coloured sand grains, loosely and irregularly arranged to form a thick wall not unlike 

 that of some tubes of T. eUersi. 



The worms attain a length of 40 mm., with a diameter of 6 mm. anteriorly, at 

 about the 8th segment ; the body begins to contract at about the 15th segment to 

 4 mm., which diameter is retained for some distance, and then it begins to taper. 



There is one point upon which I lay stress in identifying the worm, and that is 

 the form of the uncinus in the anterior segments ; the great length of the basal process 

 which starts below the teeth of the uncinus, seems to be characteristic, 



