140 Prof. Mcintosh's Notes from the 



North Sea *. 



Station 18 a. 455 ra. No. 29. 18.G.1906. Procured 

 with tl)e small trawl. 



The shelly tubes of this form exactly resembled those 

 of the other varieties. The annelids, whose bodies were of 

 moderate lenjith, are characterized by the free develojiment 

 of the branchije, which possess larue filaments, and long and 

 rather slender pinnse with scarcely a trace of enlargement 

 at the tips. The filaments do not appear to sliow any 

 glandular tliickenings such as occur in Salmacina oedtficatrix. 

 At the extremities the filament, which is comparatively 

 broad at the last ])inn;i, gradually tapers to a blunt point. 



In one example with eight pairs of anterior l)ristles the 

 two dorsal filaments were modified in an interesting manner, 

 since one presented a somewhat thick terminal process, the 

 tip of which was abruptly bevelled mainly ou one side, the 

 tapering tip being rather blunt, its cellular structure other- 

 wise remaining the same as its neighbours ; whilst the other 

 had advanced a stage further, the clavate tip being unequally 

 bevelled and hollowed so as to form a rudimentary operculum. 

 This example carried ova well forward in the posterior region, 

 but as it was imperfect, too much reliance need not be given 

 to this feature. The region frequented by this colony 

 seemed to be highly favourable, for in another example the 

 tips of the branchial filaments were irregularly enlarged. 



Station 18 a. 14.3.1907. Trawh 



l']yes present. 



The type consisted of comparatively short bodies, with 

 seven pairs of anterior bristles, and about twenty-five seg- 

 ments posteriorly, comparatively long branchinl fans — fully 

 half the length of the body, and with opercula. The form 

 of the opercula, however, varied considerably from the thin, 

 translucent, and more or less circular or hoof-shaped cup to 

 a long vase with a tapering process on the lip, a bluntly 

 clavate termination, or a cone at the end of the filament. 

 The short b(jdies are teriv.inated by the two anal papillae. 

 So far as could be observed, no reproductive elements were 

 present. Food was abundant in the stomach, aud the 

 intestine had the elliptical foecal masses. 



The structure of the collar-bristles is identical with that 

 in the St. Andrews examples. 



Station 10. 27.5.1907. 



These were characterized by small, thin, wineglass-shaped 



* I am indebted to Prof. D'Arcy Thompson for the opportunity of 

 exaniiuiu'r these. 



