84 Prof. M'Intosh's Notes from the 



and Claparede's, have each distinctive features, yet some of 

 these may be due to imperfections in observation and to 

 variation. Certainly the bristles and hooks are very similar. 

 1'he occurrence of mature females in Claparede's small form, 

 also recently procured by ]\Ir. Southern, may be connected 

 with racial distinctions. Moreover, the inconspicuous 

 cephalic ridge and the presence of eyes in it, and their 

 aljsence in Alalmgren's form, is another source of dubiety. 

 The Canadian, the Arctic exanij)les procured by the 'Valo- 

 rous,'' and the P. pJumosa of Sars all j)rcsent such a ridge, 

 and it is possible Malmgren may have overlooked it, sipce 

 in some it is inconspicuous. 



(3) On the British Amphictenidae. 



The British Amphictenidse comprised but two species 

 in Dr. Johnston's ' Catalogue of Worms in the British 

 Museum/ viz. Pectinaria betgica, Pallas, and P. graMilata, L. 

 = Amphictene ouricoma, O. F. Miiller. The latter species 

 and Lagis koreni, Alalmgren, again, were the only forms 

 entered in the 'Fauna of Plymoutli' (1904), but Mr. Craw- 

 shay in 1912 added a third, viz., Petta pusilla, Malmgren. 

 Two species occur in Mr. Southern's 'Annelids of Dublin 

 Bay,' viz., those mentioned by Dr. Johnston. 



The first species is Pectinaria belgica, Pallas, from various 

 parts of the English, Scotch, and Irisli coasts. 



The crown in this species has ten to fourteen paleolae, which 

 are broader than those of Lagis koreni, and, as P. belgica is 

 often larger, they arc stronger and more individualized^ but 

 their curves are similar, tlic convexity being ventral. They 

 dilate a little above the base, and tlien taper to a very delicate 

 hair-like tip, which, from the lines at its sides, would seem to 

 indicate relationship witli a winged bristle. Friction, how- 

 ever, removes the delicate extremity in some. The outer 

 paleola is shorter than the adjoining one, whilst the two 

 iniu'r aj)| ear also to be smaller in most examples. In the 

 larg( st example from British waters in my coll(\:tion, viz. 

 from Loch Linnhe, fcuirteeu paleola; occurred on the left and 

 ten on the right. Above the palcolaj is tiie tough, firm, and 

 slightly corrugated surface of the crown, which lias a j)ro- 

 portionally broa(h;r rim than in L. koreni. Having reached 

 its greatest diameter laterally, it curves ventrally a little 

 within the edge of the jialeohe, and ends at the long anterior 

 eirrux. The margin dorsally and laterally is smooth, but on 

 the ventral curve to the paleohr it lias one or two small 

 papilla;. 



