133 Prof. M'lntosh's Notes from the 



older examples without a bud the anterior roj^ion had seven 

 pairs of bristles l)esi(ies tiie collar pair, a considerable smooth 

 region, and fifteen segments and the pygidiuin posteriorly. 

 'I'he branchite were well developed, with sausage-shaped en- 

 largements of the tips of the filaments, and the pinnae were 

 much longer than in the former. The apertures of some 

 of the tubes show a slight expansion like the muzzles of 

 old-fashioned shot-guns for sparrows, whilst others have 

 cylindrical t'lough rounded margins. In the first series 

 of bristles, which in lateral view have the tip at an angle 

 to the shaft, the basal part of the wing has numerous 

 (fully a dozen) serrations sloping from the base to the 

 distal end in lateral view, and then a hiatus, followed by 

 a minutely serratc^d tapering blade. When viewed from 

 behind, the shaft diminishes little to the end of the basal 

 section of the wing, and the axis can be followed, as distinct 

 from the wing, from the base to the tip, and then gradually 

 tapers distally. Certain views point to the double nature 

 of the basal expansion, serrations being seen on both sides. 

 It may be that something similar exists in the distal wing. 

 What have been mentioned elsewhere as simple bristles 

 in this tuft are apparently only developing forms of the 

 special type. 



Channel Islands (off Guernsey and between tide-marks, 

 Herm). 



Most form fixed tubes on shells and stones — two opercula, 

 as a rule, on each ; these may be large and thin, or less 

 expanded as circular discs. No enlargement of the tips of 

 the other filaments. This form is common under stones (to 

 which it is attached) between tide-marks in the Channel 

 Islands. Ova occur in tlie posterior region of body. In the 

 structure of the collar-bristles no distinction can be drawn 

 between these and the Plymouth forms. The shaft, basal 

 wings, and tip are the same. The hiatus and the mode of 

 origin of the distal part of the wing agree, as also do its 

 minute serrations. 



St. Andreivs. 



Branchiae without an operculum in two bearing buds ; 

 tips of branchice cylindrical in some, in others slightly 

 clavate (in the spirit-preparations). The condition of the 

 branchiss depends on age ; in young examples the filaments 

 and pinnse are short, but they vary, some of the same size 

 of body having larger and better-developed branchiae. The 

 young have a short body. The collar-bristles show several 

 Avith curved tapering tips, which do not have the gap 



