REPORT ON THE ASTEROIDEA. 1 1 



conspicuous aud decided in the variety. The madreporiform body has not the slightly 

 convex character noticed in the type, and less convolution is present in the striatums, 

 which have a more or less regular appearance of centrifugal radiation. The tube-feet 

 have a smaller terminal knob. 



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

 Maryland. 



Station 44. May 2, 1873. Lat. 37° 25' 0" K, long. 71° 40' 0" W. Depth 1700 

 fathoms. Blue mud. Bottom temperature 36 0, 2 Fahr. ; surface temperature 56°"5 Fahr. 



Station 45. May 3, 1873. Lat. 38° 34' 0" N., long. 72° 10' 0" W. Depth 1240 

 fathoms. Blue niiul. Bottom temperature 37°'2 Fahr. ; surface temperature 49°"5 Fahr. 



2. Pararchaster antarcticus, n. sp. 



This species is very closely allied to the preceding one, and it is not without some 

 hesitation that I have ventured to place it as distinct, for unfortunately only two 

 examples were obtained, one much broken and imperfect, the other immature. The 

 former of these is consequently the only one available for comparison with the preceding 

 species, and this it resembles so much in general character that I have not considered it 

 necessary to give drawings of the mutilated specimen. 



The form is smaller than Pararchaster semisquamatus, its minor radius measuring 

 11 "5 mm. . (All the rays are imperfect, and from what remains they appear to have been 

 probably shorter and more tapering than in that species.) The abactinal area of the disk 

 is slightly inflated and convex, instead of flat, and the general character of its spinulation 

 accords much more closely with that of Pararchaster semisquamatus, var. occidentalis, than 

 with the type-form of that species. The large spines upon the disk are confined entirely 

 to the central area, and not many more than those on the basal, radial, under-basal, and 

 dorso-central plates are present. The single central spinelet on the abactinal plates along 

 the ray is short, robust, and subcorneal, and the plates appear comparatively larger in 

 proportion to the size of the animal than in Pararchaster semisquamatus. The lateral 

 walls at the summit of the interbrachial arc are vertical, and do not bend over to form a 

 bevel on the abactinal surface. The lateral walls generally along the ray are low, giving 

 the ray a very flat appearance. The supero-marginal plates beyond the sixth (from the 

 odd median interradial plate) bear two spines side by side, which may be either equal or 

 one less than the other ; and even in those plates where this second spine is not present 

 in the form of a definite large spine, it is represented by a small miliary spinelet, and of 

 these there may also be one or more additional on the plates which bear the two large 

 marginal spines. On the actinal surface of the adambulacral plates three large spines 

 are not unfrequently present. On the surface of the infero-marginal plates, and parallel 

 to the upper adoral sloping margin, is a lineal series of three to five small thorn-like 

 denticles or spinelets, which, although sometimes less conspicuously marked, are still a 



