196 



on the back of the disc, a conspicuous rosette of round, primary 

 scales. 



This species differs from A. occidentalism in its notched under 

 arm-phites, sharp spines, and prickly scales of the disc. It is a 

 somewhat aberrant species, and by its prickly scales approaches 

 Amphiura scahriuscula. 



Locality, Puget Sound. Dr. Kennerly. 



Smithsonian Institution, No. 1041. 



Amphiura Wurdemanii, (Lyman,) sp. nov. 



Description of a Specimen. Diameter of disc, 9.5 millim. 

 From outer edge of mouth-shield to outer corner of opposite 

 mouth-slit, 3.5 milhm. Width of arm, without spines, 2.2 millim. 

 Arms remarkably flat, wide, and little tapering ; as they were 

 broken, the length could not be known, but it seemed not less 

 than ten times the diameter of the disc. Teeth broad and flat, 

 with free edge a little curved. Mouth-papillae 3 on each side, 

 rounded and bead-like ; innermost one placed below the teeth, and 

 running somewhat upward. Mouth-shields shaped something like 

 the sole of a shoe, very long and narrow, small, with their outer 

 end rounded, and their inner one a rounded point, wider within than 

 without ; length to breadth, .8 : .5. Side mouth-shields almost as 

 large as mouth-shields proper, broader without than within, some- 

 what curved. Under arm-plates squarish, rather broader than long, 

 overlapping each other a little ; outer side bounded by a slight- 

 ly reentering curve, corners rounded ; length to breadth, (13th 

 plate,) .5 : .7. Upper arm-plates very short and broad, overlap- 

 ping, bounded without by a reentering curve ; outer corners 

 strongly rounded, length to breadth, .4 : 1.7 ; they are occasion- 

 ally broken in two. Scales of disc fine, of pretty even size, rather 

 thicker than are usually found in the genus ; those below some- 

 what finer ; around edge of disc, a little fence of small, flat, nar- 

 row scales, or papillae, standing upright ; this fence is interrupted 

 opposite the radial shields. Radial shields broad, blunt, pear-seed 

 shaped, sometimes separated by a wedge of three or four scales, 

 sometimes joined by their sides ; length to breadth, 2 : 1. Arm- 

 spines 3, short, stout, broad, rounded at the end, somewhat flat- 

 tened, a little longer than joints, nearly alike in shape and size. 

 Tentacle-scales 2, short, broad, and thin, with curved edges. 



