273 



rib at the anterior end of the axis. In small specimens the axis is without 

 any trace of ribs, but in the largest seen there are indications of eight or 

 nine very obscure grooves on the sides, extending obliquely inwards and 

 forwards ; none on the side lobes. The apex of the axis is sometimes 

 Indistinctly defined. 



The largest specimen seen is 10 lines in length, and 17 in width. 



Locality and Formation. — N, Table Head, and P, four miles N.E. from 

 Portland Creek, Newfoundland ; Quebec group. 



Collector. — J. Richardson. 



NiLEUS MACROPS. (N. Sp.) 

 Fig. 259. 



Description. — Head sub-semicircular, length a little greater than half 

 the width, rather strongly convex, posterior corners sub-angular or very 

 narrowly rounded ; eyes semiannular, their length equal to three-fourths 

 the whole length of the head, their posterior angles about one-fifth their 

 length from the margin ; they are situated near the side of the head. 

 There is a small rounded tubercle about the centre of the upper side of 

 the head. 



Thorax of seven segments ; axis obscurely defined, and a little more 

 than half the whole width. 



Pygidium transversely sub-oval, length scarcely half the width, uni- 

 formly depressed convex, broadly and uniformly rounded behind, and 

 apparently facetted on the anterior margin near the angle. 



Several imperfect specimens have been collected. They ate about 12 

 lines in length, and 7 in width. Length of the head 4 Imes, and of the 

 eye 3 lines. 



This species differs from N. scrutator in having the eye much larger, 

 and from N. armadillo in having only seven instead of eight segments in 

 the thorax. 



Locality and Formation. — N, Table Head, Newfoundland; Quebec 

 group. 



Collector: — J. Richardson. 



