OPHIUEANS OF UNITED STATES NATIONAL MUSEUM. 59 



through the upper bracliial plates being narrower, and, lastly, through the slight 

 development of tlie tentacular scale, wliich is always single beyond tlio fu^t five or 

 six bracliial articles, while it remains double, in A. hihamula, on two-thirds of the 

 length of the arms. 



I have described recently, under tlie name of A. l-uhentlali (13, p. 386), an 

 Am'plnura, tlic under face of tlio disk of wliich is covered witli fine and rc'ular 

 scaling, extending uninterruptedly until it joins tjie upper plates, an arrangement 

 very different from the one observed in A.fihulata. In tliis new species, the bracliial 

 spines, which come after the fu-st ventral one, bear at their ends a well-developed 

 distal hook, and sometimes also a httle proximal hook, which give to some of the 

 specimens a bihamuled appearance, though never so clear as that of A. jibulata or 

 of A. hihamula; besides, tlie two tentacular scales are most regidarly continued on 

 the longest part of the arms. In short, the two species are altogether tlifferent 

 from each other. 



I have found in the collections of the United States National Museum a small 

 A. kulcentJiali, wliich I mention below. 



AMPHITTRA Kt)KENTHALI Ecehlet. 

 Amphiura kiihenihali Kiehler (13^, p. ;i90, pi. 20, figs. 1-4. 

 Key West, Florida. One specimen. 



The specimen is of very small size and the diameter of the disk does not exceed 

 4.5 mm., but it entirely agrees ynth the larger specimens from the West Indies, 

 from wliich I have just described the species. It was associated with other Oplii- 

 urans: AmpTiiura abdita, Amphiura stimpsoni, Ophionereis reticulata, and Ophio- 

 stigma isacanthum. 



AMPHIPRA COMPLANATA Ljungman. 



Plate 5, llge. 3-6. 



Amphiura complanata Ljungm.\n (66), p. 319. 

 Amphiura complanata Ljungman (71), p. 642. 



Albatross station 2762. December 30, 1887. Lat. 23° OS' S. ; long. 41 ° 34' W. ; 

 59 fathoms; bu. m.; temp. 57.1° F. Several specimens. 



A very short description of tliis species, wliich, however, is sufficient to recognize 

 it, has been pubUshed by Ljungman. I wanted, nevertheless, to compare my 

 specimens witli tlie tyiie which is preserved in the Stockliolm Museum, and wliich 

 has been most obhgingly communicated to me by Professor Theel. Ljungman's 

 description being very short, I tliink it useful to describe the species with a few 

 more details from tlie specimens gathered by the Albatross. 



The diameter of the disk generally varies from 7 to 8 mm., and it can reach 

 10 and 11 mm. In some examples, the disk of which is 10 mm. wide, tlie length of 

 the arms is from 75 to 80 mm. 



The disk is flattened, ratiier tliick, strongly excavated in theinterradial spaces, 

 and it also shows some sharp notches above the insertion of the arms. The upper 

 face is covered with numerous, small, unequal, and imbricated plates which are 

 smaller at the center and toward the margin in the interradial spaces, and, on the 

 contrary, larger near the radial sliields. On the samples of small or middling size, 

 may be seen a rosette of six primary plates; the centro-dorsal one is rounded and 



