ARENICOLA MARINA. 67 



in size from before backward ; the seventh is decidedly broader than the sixth and the 

 papilla somewhat more prominent. From the eighth backward the papillse appear to be 

 very prominent and the rows of hooks about equal in breadth ; moreover they nearly meet 

 in the middle line. The hooks (Plate OIII, fig. 11 d) have a golden colour, a shape some- 

 what like that of a golf-club with the handle bent back (the basal part of the hook). 

 About the middle of the hook a gradual and slight enlargement occurs with well-marked 

 oblique striation and a series of transverse lines. The oblique striaa pass to the distal curve 

 of the hook, the tip alone being free, and they also proceed downward to the insertion. 

 Two, three, or four minute spines occur on the convex part of the rostrum. Friction 

 seems to render these indistinct and make a blunt tip to the rostrum. The enlarged 

 part of the hook appears to coincide with that bearing the strain at the edge of the ridge 

 into which it is inserted. 



Nephridia. — Each consists of a funnel or nephrostome, a secreting portion, and 

 a posterior terminal vesicle or bladder. It is always bright red from its vascular supply. 

 A comparatively recent and excellent account with figures is given by Dr. H. M. Kyle. 1 

 Gamble and Ashworth 2 place the external opening of these organs behind and at the upper 

 edge of the ventral division. 



Ashworth notes the differences presented by the hooks of young forms in which the 

 angle formed by the rostrum is much less than in adults and the secondary spurs on the 

 crown are longer. Moreover a spur occurs beneath the rostrum. In the post-larval 

 A. marina there are besides the ordinary bristles one winged form with faint oblique 

 striations on the wings. This caused Mesnil to make a new species (Glymenldes sulfureus) 

 of this stage. In the post-larval hooks two or three teeth occur behind the beak and a point 

 under the beak. In old specimens no teeth exist above, but the sub-rostral point is present. 



At Lochmaddy, North Uist, not only are the ordinary coils of sand abundant in the 

 creeks, but many in hollows are on the summit of considerable mounds of smooth sand, 

 and thus the areas are very rugged. The mounds are probably due to the gentle flow 

 and ebb of the tide, and to the fact that the areas in the creeks referred to are generally 

 surrounded by stones covered with Fuci. The absence of anything like a " run " or rush 

 of the advancing or retiring tide would appear to favour this condition. 



Everywhere around the British and European shores this form is employed as bait 

 for codling, plaice, and other fishes. In searching, the men look for the " eye," or 

 anterior hole, a little cup-shaped depression in the sand, at some distance — 9 — 12 in. 

 — from the casts. At St. Andrews the men consider that when the wind blows from the 

 east it is difficult to see the " eye," or anterior hole, as the sand is soaked, but it is other- 

 Avise in a west wind. They dig rapidly from the " eye " to the casts, and generally find 

 the anterior end of the worm near the curve of the tube. Lately a different method has 

 been followed, for they actively dig round the cast until the hole is seen. If the work is 

 slowly carried out the worm makes a fresh tunnel in the sand and escapes. 



In confinement the worms perish rapidly if left in the collecting vessel, and even 

 when spread out on a board amongst moist sand they survive only for a day or two, e.g. 

 from Saturday to Monday, and even then it is considered that they are less effective. 



1 ' Ann. Nat. Hist./ ser. 6, vol. xviii, p. 295, pis. xiii— xv, 1896. 



2 ' Quart. Journ. Micr. Sci./ vol. xli, n.s., p. 509, 1899. 



