206 



lowing the subdivision become more prominent on the 

 supraradial plates. The sides of the radial plates are 

 marked by similar but less defined elevations extending to 

 the sutures, and meeting similar ridges on the interradial 

 plates. There are rarely some intermediate folds or unde- 

 fined ridges upon the surface of the plates. 



The surface has no peculiar markings. The column in its 

 upper part is cylindrical, composed of unequal joints, which 

 often appear to be made up of unequal or irregular plates. 



This species differs from G. occidentalis and from G. brach- 

 iatus in the absence of surface sculpturing, nodes or granules ; 

 in the greater development of the basal plates, and the 

 quadrangular form of the second radial. 



GENUS MELOCRINUS (Goldfuss). 



Melocrinus obconicus {Hall). 



Body narrowly subturbinate or obconical, basal plates form- 

 ing together an elongate quadrangular prominence, which 

 scarcely expands above, and from which the body gradu- 

 ally enlarges to the base of the arms. Radial series of 

 three plates each, the first of these heptagonal, and the 

 largest plates in the body ; second radials a little smaller 

 than the first, octagonal ; third radials much smaller, 

 heptagonal and supporting on each upper sloping side a 

 series of two supra-radials, the upper one apparently 

 a bifurcating plate in some of the rays. 



The interradial series, in three of the areas, are one, one, 

 and two or three, and in the other two specimens, one, two 

 and three or four. The summit is pentalobate, covered by 

 small plates, and showing the base of a slightly excentric 

 proboscis. The piates of the body are smooth in the mid- 

 dle, with short abrupt angular ridges near the margin, 

 which meet similar ridges of the adjoining plates, at the 

 suture lines. 



In size this species is but little more than half an inch 



