778 " THETIS " SCIENTIFIC RESULTS. 



fourth and following about as long as bioad ; fourth and follow- 

 ing segments with a median transverse dorsal ridge, appearing 

 like a small spine in lateral view ; at first the apex of this ridge 

 is practically a straight line, but later it becomes gradually more 

 and more convex and at the same time narrower, so that on the 

 terminal segments it resolves itself into a laterally elongated 

 centrally arched tubercle ; opposing spine short but prominent ; 

 median, erect, equal in height to about one-fourth the lateral 

 diameter of the penultimate segment; terminal claw slightly 

 shorter than the penultimate segment, stout and rather abruptly 

 cui'ved proximally, becoming slender a.nd nearly straight distally. 



Radials plainly visible, between two and three times as broad 

 as long J IBr^ trapezoidal, about twice as broad as long, basally 

 in lateral apposition, gradually separating distally ; IBrg broadly 

 pentagonal, about one and one-half times as broad as long. 



Ten arms about 25 mm. long; first brachial wedge-shaped, 

 interiorly united for almost its entire length ; second brachial 

 similar, but proportionately longer ; third and fourth brachials 

 (syzygial pair) about as long as broad, oblong ; following brachials 

 to the eighth oblong, about twice as broad as long, then becoming 

 triangular and about as long as broad, and wedge-shaped and 

 longer than broad distally ; synarthrial tubercles more or less, 

 but never strongly, developed. 



Syzygies occur between the third and fourth and seventh and 

 eighth brachials, thence at intervals of from three to five (usually 

 four) oblique muscular articulations. 



Pj comparatively long and stout, tapering uniformly from the 

 base to the tip, with twelve segments, the first about as long as 

 broad, the second half again as long as broad, the third and 

 following about twice as long as broad (slightly more proximally, 

 slightly less distally) ; Pg similar, but considerably shorter with 

 eight segments, the first squarish or not quite so long as 

 broad, the second about half again as long as broad ; the 

 remainder about twice as long as broad ; P3 shorter than 

 Pg with about twelve segments, the first not so long as broad, 

 the second to the fifth about as long as broad and rather stout, 

 the remainder longer than broad ; P4 similar, but the third and 

 fourth segments are slightly broader ; following pinnules with the 

 third and fourth segments laterally expanded forming a roof over 

 the genital glands ; the fifth segment is expanded proximally but 

 tapers distally, and the remaining segments are slender. This 

 swollen and expanded condition of the pinnule segments persists 

 practically unchanged to P15, at which point the arms of the 

 specimens examined are all broken oflT. 



The colour (in spirits) is yellowish-white, transversely banded 

 on each segment with purple, rarely entirely yellowish-white or 

 entirely purple. 



