7 2 NATURAL HISTORY BULLETIN. 



Under arm-plates, near the base of the arms, trapezoidal 

 with convex outer edge and rounded corners, usually rather 

 longer than broad; farther out they are nearly square, a little 

 separated by the side plates. 



Oral shields five-sided, broader than long, outer edge a 

 little convex, angles rounded; inner edges concave, meeting in 

 a broad angle. Adoral shields large, rudely ovate, the nar- 

 rower inner ends broadly in contact. Mouth-papillag about 

 five, angular, acute, more or less flattened. 



Genital pores very small, round, under the outer end of 

 the oral shield. 



Color deep brown, variously spotted with whitish, imitating 

 the colors of Gorgonclla to which it clings. 



Usually many of the more prominent verruciform plates of 

 the upper side of the arms and disk are white; under arm- 

 plates dark brown. 



Station i^ and 16, off Havana, 200 fathoms, two examples. 

 Taken by the Blake Expedition in 96 and 115 fathoms. 



Sigsbeia murrhina Lyman. 



Sigsbeia murrhina Lyman, Bull. Mus. Corap. Zool., V, 9, p. 234, 1878, 

 pi. Ill, figs. 55, 58; op. cit. X, p. 277; Lyman, Report Voy. Chal- 

 lenger, Zool., Ophiuroidea, V, p. 250, pi. XLIII, figs. 4-6, 1882, 

 anatomy; Three Cruises of the Blake, II, p. 114, fig. 399, 1888. Nut- 

 ting, Narrative, p. 79. 



Plate II; Figures i, \a. 



Station 13, off Havana, 200 fathoms, one adult and one 

 young; station 73, Little Cat I., 3 to 15 fathoms, three young. 



This species clings to gorgonians, which it imitates in form, 

 and probably in color when living. 



A young specimen, having a disk 3.5 mm. in diameter, ap- 

 pears to belong to this species. It is from station 73. 



This specimen differs so much from Mr. Lyman's figures 

 that it might almost be taken for a new species, but the differ- 

 ences may be due to age. 



