66 NATURAL HISTORY BULLETIN. 



Lyman, Bull. Mus. Comp. Zool., V, 9, p. 233; Lyman, Report, Voy. 

 Challenger, Zool., Ophiuroidea, V, p. 246, pi. XLIU, fig". 1-3, 1882, 

 anatomy. Nutting-, Narrative, pp. 132, 170. 



The specimens of this species show, in alcohol, consider- 

 able variation in color; most of them are dull yellowish green, 

 or dark olive green on the disk, more or less mottled with 

 yellow, and frequently with rings of yellow on the arms. In 

 some examples the whole disk i s covered with irregular 

 rings of light yellow on an olive green ground-color. The 

 colors are usually reddish or orange in life. In the larger 

 specimens there are often, on alternate joints, four and five 

 spines on each side; beyond the middle regularly five, or five 

 and six on alternate joints more distally. 



Tortugas, in shallow water, ten large examples, Egg Key, 

 young. 



Common in shallow water from the Florida Keys to the 

 Abrolhos Reefs, Brazil, and throughout the West Indies. 

 Bermuda (coll. Goode). 



Ophiomyxa brevicauda Verrill, sp. nov. 

 Plate III; Figure 3. 



Arms relatively short and stout, rapidly tapered. Disk 

 relatively large, tumid, five-lobed, extending out on the arms, 

 covered with thick wrinkled cuticle, which contains few 

 scales except along the margin and at base of arms, where 

 there is a row of rather stout scales. Radial shields small, 

 obscure, roundish. Arms covered above with smooth cuticle, 

 without upper arm-plates or granules; the rhombic surfaces of 

 the internal plates show a median groove and are nearly in 

 contact. Under arm-plates small, rather shield-shaped, with 

 a deep distal notch and angulated outer corners. Side-plates 

 large, thick and prominent. Arm-spines three, webbed to- 

 gether, and covered by cuticle, slender, very acute, glassy, 

 roughly serrulate. Tentacle-pores rather large. 



Mouth-papillee four, sometimes with a minute fifth distally; 

 they are wide, flat, subtruncate or rounded and finely serrate 

 at the end. 



