66 BtTLLETIN 84, UNITED STATES NATIONAL MUSEUM. 



together, and it becomes a little wider proximally. The succeeding plates are at 

 first quadrangular with well-rounded angles, and a little longer than wide; they 

 then become pentagonal, with a truncated proximal angle, although they still remain 

 somewhat longer than wide. 



The lateral bracliial plates, fairly wide, each bear seven spines and sometimes 

 eight at the basis of the arms. These spines are short, nearly equal and their 

 length is next to that of the article ; however, the dorsal spines grow slightly shorter 

 down to the last ones. They are slightly flattened and their surface is rough. The 

 lateral spines, and above aU the second under spine, are often provided near the 

 rounded end, with two very small diverging denticulations which give them a 

 bihamuled appearance, but this structure is always little developed; sometimes 

 the small denticulations appear on one side only. 



The single tentacular scale is thin but fairly long, conical, with an obtuse point; 

 its length does not reach half the corresponding under brachial plate. 



Cormectioits and differences. — A.diducta belongs to the gi'oup of the AmfMurBE, 

 s. str., which possess but one tentacular scale and have the under face of their disks 

 bare. It differs from the forms of that gi'Oup which, by the way, are few, in having 

 numerous brachial spines, large and elongated radial shields and also a fairly long 

 tentacular scale; I see no species to which it might be allied. 



AMPHIPHOLIS (-AMPHrURA) SQUAMATA (Delle Chiaje). 



See for bibliography: 



Koehler (09), p. 179. 



SiiBsbach and Breckner (11), p. 253. 



Kcehler (13), p. 356. 



Albatross station 2645. Apr. 9, 1886. Lat. 25° 46' 30" N.; long. 80° 02' W.; 

 157 fathoms; gn. s.; temp. 43.4° F. One Uttle specimen. 

 Key West, Florida. One little specimen. 



AMPHIPHOLIS (=AMPmURA) TENmSPlNA Liungman. 



See for bibliography : 



Kcehler (98), p. 53, pi. 6, figs. 22-23. 



Albatross station 2619. Oct. 20, 1885. Lat. 33° 38' N.; long. 77° 36' W.; 

 15 fathoms; crs. yl. s. brk. sp. rot. co. One specimen. 



The sample, Avhich is of very small size, is identical with the one which Verrill 

 represented (85, pL 20, fig. 53). 



AMPHIPHOLIS (=AMPHnjRA) GRACILLIMA (Stimpson). 



Amphiura grucilUma Lyman (65), \). IIG. 

 Amphiura gracillhtia Lyman (75), pi. 5, fig. 70. 

 Amphiura gracillima Lyman (82), p. 146. 



Fish Eawlc station 7109. Mar. 29, 1901. Tampa Bay, Florida; 6* fathoms; 

 mud; temp. 20.5° C. Two specimens. 



In both specimens the upper face of the disk has been torn away, but the 

 characters of the mouth pieces and of the arms allow, however, the determination of 

 the species with all the certainty which one might wish for. 



