OF THE SIBOGA-EXPEDITION, 155 
furrow; the IBr, are proximally about as broad as the 
lateral length but distally slightly broader, not quite twice 
as broad as the median length; the lateral length is half 
again as great as the median length due to the incision 
by a process from the axillary; the lateral edges are straight, 
diverging somewhat, entirely free; the axillaries are rhombic, 
the lateral angles slightly truncated and continuing in the 
same direction as the lateral edges of the IBr, ; the anterior 
angle and the process incising the IBr, are about equally 
produced, and the proximal and distal sides are slightly 
concave. 
The ten arms are all broken; the first brachial is wedge- 
shaped, about as broad as the exterior (greater) length 
which is about twice as great as the interior length; the — 
inner edges are entirely free; the second brachial is larger, 
irregularly quadrate; the third brachial is nearly twice as 
long interiorly as exteriorly, and about as broad as the 
exterior length. 
The total length of the animal from the tip of the 
centrodorsal to the syzygy between the third and fourth 
brachials (at which point all the arms are broken off) is 
9 mm. 
Type locality. — »Siboga” Station N°. 177. 
Washington, February 1912. 
Notes from the Leyden Museum, Vol. XXXIV. 
