77 



Anteriorly the paluliv are fourteen on each side, set in a sliglitly 

 oblique row, and with a dorsal curve. Each group forms a 

 kind of stiff fan with the longest palea' in the centre, the outer 

 especially being shorter. A typical palea measures about 15 

 mm., is flattened and of a rich golden colour, iridescent under 

 the microscope, and marked with longitudinal and transverse 

 stria'. The tip is usually abraded — forming a transverse dark 

 edge. A wrinkled area slopes obliquely downwards, and is 

 bounded by a membrane which commences at the subulate 

 tentacle a little in front of the outer edge of each fan, and has 

 its free edge cut into processes, small at first and then triangular 

 and larger. Below the palea is a broad membranous fold with 

 long filaments at its free edge, which encircles the two dense 

 groups of tentacular cirri. 



The body is broad in front and tapers after a short distance 

 gently to the tail, which ends in a sausage-like appendage, 

 having a broad furrow with thick folded edges dorsally, and 

 terminating in a tongue-like flap with a wide crenated margin. 

 Beneath the process is marked by fine creases (like leather) and 

 has a median groove and three lateral furrows which slope 

 outwards and backwards. 



Anteriorly the dorsum has an elevated glandular whitish 

 thickening from which a tapering tentacle extends forward. A 

 ridge cut into flaps passes from the elevated mass and joms the 

 pre-oral fold. Another smaller whitish pad occurs behind the 

 former to the inner side of the first branchia. The latter is the 

 larger, and arises from the ventral ridge behind the mouth, is 

 fixed for half its length, the other or outer part passing as a free 

 fold dorsally. From the basal stem the branchial tissue splits 

 into fine lamella, so that aeration is readily carried out. The 

 second gill is similar to the first, but arises from the succeeding 

 glandular ridge further out, and its free stem extends further on 

 the dorsum. On the ventral surface in this region are four small 

 central areas or cushions connected with conspicuous bands 

 passing dorsally. The first lies in the ridge behind the mouth 

 and has a frilled (glandular ?) band in front of it, connecting 

 the inner (ventral) ends of the first branchia. The second has 

 a stift" glandular ridge passing from its anterior border to the 

 second branchia. The thuxl is the least, and from its outer 

 border a prominent fillet passes to and beyond the first bristle- 

 bundle on each side. The fourth is shield-shaped, and from its 

 anterior edge a flattened fillet extends to the side of the body, 

 but doe.s not reach the second bristle-bundle. 



Sixteen pairs of bristle-bundles extend along each side, thus 

 the number differs from that found in Pcctiiun in, where it is 17, 

 the same niuiiber occurring in Amphktouc Cisfciiidt's and Pisfa, 

 whilst Lngis has only 15. This form therefore occupies an 

 intermediate position in this respect, though most nearly ap- 

 proaching Av////^//7V/ (Plate VII). The bristles (fig. 33 a and h) 



