270 BULLETIN OF THE 



Station 203, Martinique, 96 fathoms, 1 specimen. Bartlett, entrance to Port 

 Eoyal, Jamaica, 100 fathoms, 1 specimen. 



The species is readily distinguished from 0. attenuatum by much wider arms, 

 and by two instead of three arm-spines. 



Ophiogeron supinus sp. nov. 



Plate VII. Figs. 103-106. 



Special Maries. — Arms very flat and covered with thick, loose skin. Two 

 glassy, slender, smooth arm-spines enclosed in a common skin-bag. 



Description of an Individual. — Diameter of disk 18 mm. Length of arm 

 about 85 mm. Width of arm near disk 5 mm. Height of arm 2.5 mm. On 

 either side of the large mouth-angle is an irregular row of minute, conical 

 papilla?; a cluster of similar tooth-papilla? stands on the jaw-plate; and, above 

 these, are small, spine-like teeth. Mouth-shields small, as broad as long, pre- 

 senting an angle within and a curve without. Side mouth-shields long and 

 pretty wide; fully meeting within; and, at their outer ends, extending much 

 beyond the mouth-shield. At base of arm all plates are quite obscured by 

 skin; but at the tip may be seen small under arm-plates, longer than broad, 

 and pentagonal, with re-entering lateral sides and an angle within. The side 

 arm-plates then meet below, but do not encroach on the upper surface. As 

 there are no upper plates, the arm-bone may be seen, divided into its two 

 embryonic halves. Disk uniformly covered by a soft, naked, wrinkled skin, 

 which was much torn in the specimens observed. Genital openings long and 

 large, extending from mouth-shield to margin of disk. Two glassy, smooth, 

 slender arm-spines, longer than a joint, and enclosed in a common skin-bag. 

 No tentacle-scales. Color in alcohol, pale brown. 



Station 148, St. Kitts, 208 fathoms, 2 specimens. Station 291, Barbados, 

 200 fathoms. Station 230, St. Vincent, 464 fathoms (young). 



The long flat arms covered by loose skin readily distinguish this species 

 from O. edcntulus. 



There are, under the skin, just over the arms, small rounded radial shields, 

 and, articulated to them, very short genital scales and plates, very much as in 

 Ophiobyrsa. In the substance of the skin are imbedded fine scales, especially 

 near the disk margin. 



Ophiohelus umbella Ln. 

 Station 300, Barbados, 82 fathoms. 



Ophiomyces mirabilis bn 

 Station 222, St. Lucia, 422 fnthnms. 



Ophiomyces frutectosus Ln. 

 Station 281, Barbados, 288 fathoms. Station 282, Barbados, 154 fathonn. 



