440 PHOLOfi MINUTA. 



The second pair are elongated transversely as in the other form, but are dis- 

 tinguished by the great length of the cilia on the outer border. A few cilia also occur 

 along the posterior edge. 



The succeeding scales in the anterior third do not differ much in shape from those 

 of P. minuta, but the cilia are much longer and stand stiffly out. They occur on the 

 external margin and the outer half of the posterior edge. They are less numerous than 

 in the large examples of the typical form, but agree with the smaller in this respect. 



The posterior scales have about the same number of cilia, but they stand stiffly out 

 like rays. 



This form is distinguished from the preceding in spirit by an olive spot on the scale, 

 with a pale centre at the scar for attachment. Occasionally, as in an example of this 

 variety from Lochmaddy, the cilia on the scales are fewer and longer, being filiform 

 tapering processes without the terminal enlargement. 



In both varieties the areolse, especially towards the inner edge, are well marked. 



Feet. — The second foot is bifid, with two well-developed spines. The dorsal lobe 

 forms a rounded eminence with a smooth surface. The bristles are comparatively short, 

 slender, and taper to a very fine hair-like tip, minutely spinous. The inner forms taper 

 more abruptly than the outer, and the tips are often bent nearly at right angles to the 

 base. The ventral lobe is longer than the former, bluntly conical, and with numerous 

 small papillae on its surface. The ventral bristles have stout shafts dilated at the tip, 

 and with numerous rows of spines on the convex margin, thus differing from those of 

 the arctic examples (P. minuta, Pabr., typical), which have few. The distal region 

 forms an elongated process — hooked at the tip, and with a series of spikes along the 

 ventral edge. The tip in the arctic forms is more robust and proportionally shorter. 



In the typical foot (Plate XXXI, fig. 14) the dorsal lobe presents a prominent 

 process and a broad, slightly convex margin externally for the bristles, the spine 

 piercing the apex of the convexity. The bristles (Plate XLII, fig. 23) form a dense 

 tuft, directed outwards and downwards, and are slender and tapering, with well-marked 

 spinous rows. 



The ventral lobe has the shape of an oblique cone, with the spine issuing from the 

 apex and with numerous papilla over the surface. The shafts of the bristles (Plate XLII, 

 fig. 24) are somewhat shorter and stouter than in the northern form (P. minuta, typical), 

 and the convex edge of the tip has more numerous spikes. The falcate tip is shorter, 

 more curved (the hook more pronounced), and the spines along the edge are often absent. 

 Indications of these, however, are seen. 



Posteriorly, the dorsal bristles have finer spikes, and the ventral have fewer rows of 

 spines at the convex distal region of the shaft, while the terminal portion is more 

 slender and proportionally longer. The papillae on the ventral division are fewer and 

 somewhat longer. The ventral cirrus is short and tapered. 



In examples from Lochmaddy only three or four spikes occur on the distal end of 

 the shafts of the ventral bristles. Some from Bressay Sound show more numerous 

 though finer spikes at the distal end of the shafts, as in those from St. Andrews. In a 

 small one from St. Magnus Bay they were too indistinct for determination, though 

 they appeared to be smooth. In a small example from Herm no spikes were present 



