30 s. goto: 



" Pararcliastcr scmîsquamcdus var. occidentalis, uov. 



" Tliere is a single si)ecimen from the western side of the North Atlantic, 

 off the east coast of North America, which, although agreeing in a remarkable 

 way in all essential xwints with the type just described, presents a number of 

 variations which render it worthy in my opinion of nominal recognition, — in 

 fact, it may ultimately prove to be a distinct species. At x^i'esent, however, 

 I hesitattî from according it that rank on the slender evidence of a solitary 

 and imperfect specimen, although the widely separated geograi^hical position of 

 the two dredging stations would cartainly favour the adoption of such a com'se. 



" The two forms are almost exactly of the same size. In the Atlantic 

 example — the variety under notice— the spines on the supero-marginal x^lates 

 are distinctly tliicker and more robust at the base, wliile those on the 

 infero-marginal jjlates are relatively smaller than in the Pacific form (the 

 tyjse). The two large spines on the actinal sm-face of the adambulacral 

 pLites are also smaller and shorter. On the abactinal sm-face the single 

 minute thornlet which springs from the centre of the abactinal plates is 

 distinctly shorter and thicker — a circumstance which gives at first sight a 

 finely tuberculate character to the abactinal area when viewed from above. 

 Tlie large spines in the central region of the disk are smaller and much 

 less numerous than in the Japanese form, and do not extend to the base of 

 the rays. The lateral wall at the summit of the interbrachial arc is much 

 less bevelled towards the ubactinal surface of the disk, and the marginal 

 plates do not bend over so conspicuously as in the type figm-ed. The infero- 

 marginal plates apixiar joroportionately smaller in their transverse dimensions ; 

 and the marginal and fm-row series of sxjines on the adambulacral plates are 

 slightly more delicate and elongate. The roughening of the siu"face of the 

 large spines on the marginal plates and elsawhere is more conspicuous and 

 decided in the varietj'. The madreporiform body has not the slightly convex 

 cliaracter noticed in the typa, and less convolution is present in the striations, 

 wliich liave a more or less regular appearance of centrifugal radiation. T'he 

 tube-feet liave a smaller terminal knob. 



" Locality. — Station 44 or 45. Off the coast of North America, east of 

 Delaware and Maryland. 



