262 



MICRONEREIS VARIEGATA. 



toward the distal end, a pale spine, and a tuft of translucent bristles like those 

 following. 



The second foot has a much larger setigerous region also enlarged distally and 

 curved, the convexity being in front in the preparation. A spine and a group of bristles 

 are also present. Claparede found a cirrus in both this and the first foot. The pre- 

 parations had lost them. 



The third bristled segment bears a bifid foot, and this condition continues to the 

 posterior region. The typical foot (Fig. 63) consists of two widely separated divisions, 

 the split proceeding almost to the base, the spine in each division arising close to its 

 neighbour, and then gently diverging to the tip of its respective lobe. The superior 

 division in the specimen from the Channel Islands is somewhat clavate — that is, distinctly 

 enlarges till a well-marked knob for the cirrus on the upper surface is reached. The tip 

 then narrows to an acute angle (in spirit) occupied by the spine, which slightly projects. 



Fig. 63. — Head and anterior region of Micro7iereis variegata, Claparede, somewhat compressed. (After Claparede.) 



The inferior division of the foot has a similar shape reversed, and the ventral cirrus 

 is about the same size. The dorsal surface of the upper division is ciliated and may 

 assist in respiration (Claparede). 



The bristles (Plate LXXXVI, fig. 8) are slender, translucent structures with a 

 slight curvature of the shaft, and an enlarged tip which is homogomph, the long, slender, 

 tapering terminal piece being sunk in the pit of the bifid region. In the example from 

 Guernsey the upper bristles (four to five) lay beneath the spine, whereas the inferior 

 bristles appear under pressure on both sides of the spine, and they are somewhat shorter 

 than the upper. As Major Elwes remarks, the tips of the bristles represented by 

 Claparede differ in being shorter, wider, and with a more distinct tendency to curvature. 



Reproduction. — Claparede's first example was a female, and he found eggs 0*08 mm. 

 m the coelome in summer (July). As mentioned below, Racovitza more recently has 

 given an excellent account of the reproduction of this form. 



This is one of the numerous discoveries of the accomplished and indefatigable 

 Claparede on the southern shores of Europe. He found a somewhat larger form (6 mm.) 

 at Port Vendres, 1 which had a third small, horny point between the tips of the 



1 ' Grlanures Zoot./ p. 122, pi. viii, fig. 4 ; 1864. 



