472 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME 1 



to the arm the IBri are somewhat over twice as broad as their lateral length. They 

 are very deeply incised by a proximal process from the axillaries so that in the median 

 line they are about as long as the radials. In profile the dorsal surface is seen to 

 extend directly outward at right angles to the axis of the arm. The IBr 2 (axillaries) 

 are shield-shaped, about as long as broad, with an obtuse distal angle and proximally 

 a long rounded swollen process deeply incising the IBrj. Strongly developed synarthrial 

 tubercles are present, and there are pronounced lateral flanges on the ossicles of the 

 division series which are continued as far as the third brachials so that the neighboring 

 arm bases are almost in contact. 



The 10 arms are 60 mm. long. The first brachials are twice as long exteriorly 

 as interiorly, about twice as broad as the exterior length, and form a large synarthrial 

 tubercle with the proximal process from the second brachials, which are roughly 

 shield-shaped, not greatly broader than long. The first syzygial pair (composed of 

 brachials 3+4) is about half again as broad as long, and is slightly longer interiorly 

 than exteriorly. The next four brachials are approximately oblong, nearly three 

 times as broad as long, after which the brachials become triangular, about as long as 

 broad, and soon very obliquely wedge-shaped until distally they become about twice 

 as long as broad, and terminally still longer. Beyond the third syzygy the brachials 

 are constricted centrally and have very finely serrate, though not produced, distal ends. 



Syzygies occur between brachials 3 + 4, 9 + 10, and 14 + 15, and distally at intervals 

 of 3 muscular articulations. 



The length from the proximal edge of the IB^ to the second syzygy is 7.0 mm.; 

 the width of the first syzygy is about 1 .2 mm. 



P, is 6 mm. long with about 12 segments, of which the first is about as long as 

 broad and is slightly trapezoidal, the second is about half again as long as broad, and 

 those following are much elongated, becoming five or six times as long as broad distally; 

 the third and following segments have moderately flaring and coarsely spinous distal 

 ends. P a is also 6 mm. long with 11 or 12 segments. P 2 is 5.7 mm. long with 11 

 segments and resembles P]. P 3 is 5 mm. long with 11 segments and resembles the 

 preceding pinnules. P 4 is 3.2 mm. long with 8 segments and resembles the earlier 

 pinnules. 



The color in alcohol is bright yellow with the cirri beyond the transition segment 

 white. 



Notes [BY A.M.C.]. Another specimen from the same station is similar in size to 

 the holotype. It has lost all the cirri except for one peripheral one, which has 39 

 segments and measures 16 mm. in length. The dorsal spines have the same crestlike 

 form as in the type. The centrodorsal is revealed as flattened hemispherical, which is 

 also how I would describe that of the holotype. The cirrus sockets are crowded and 

 though some appear to be placed in columns, just as many seem to alternate. This 

 specimen also has large synarthrial tubercles on the division series and first two 

 brachials as well as the lateral flanges extending to the third brachials. 



Locality. Mabahiss station 157; John Murray Expedition; Maldive Islands (lat. 

 443'48" N., long. 7255'24" E. to lat, 444' N., long. 7254'18" E.); 229 meters; 

 coral rock; April 6, 1934 [A. H. Clark, 1937] (2, B.M.). 



Remarks [by A.M.C.]. Since the type and only specimens of both Adelometra 

 angustiradia and Caryometra robusta are in the British Museum, I was able to compare 

 them. Mr. Clark had decided (MS.) that they are both congeneric with the West Indian 

 species of Caryometra. I presume this decision was made since his 1940 paper on 



