•75 
b- distal cirrus segments broader than lon;^-, and bearing a high narrow 
sharp keel the crest of which is parallel to the axes of the segments; 
each of the elements of the division series bears a more or less developed 
low rounded median tubercle (southern Japan; ? depth) .... septenlrionalis 
1. Crossometra inz'cstigatoris (A. H. Clark). 
A. H. Clark. Proc. Biol. Soc. Wasliington, vol. 22, 1909, p. 82 {Pacliyloinctra tiivistigaloris). 
Proc. U.S. National Museum, vol. 39, 191 1, p. 556 [Pachylometra lima). 
Crinoids of the Indian Ocean, 1912, p. 216, fig. 39, p. 217 (Pachylometra investtgaloris). 
Stat. 297. io°39S., 123° 40' E. Timor Sea. 520 Metres. 3 PIx. 
The largest specimen has 20 arms 110 mm. long; there are no llIBr series; the cirri 
are 30 mm. long with 22 — 23 segments; another has 21 arms; the third has 18 arms about 
90 mm. long. 
2. Crossometra helms (A. H. Clark). 
.V H. Clark. Proc. Biol. Soc. Washington, vol. 25, 191 2, p. 78 [Pachylometra helius). 
Stat. 254. 5°4oS., 1 32° 26' E. 310 Metres. 5 Ex. 
The centrodorsal is of moderate size, flattened hemispherical or thick truncated conical, 
6 mm. in diameter at the base, 3 mm. across the flat dorsal pole and 4 mm. hio-h; the cirrus 
sockets are arranged in ten equally separated columns of two or three each. 
The cirri are about XXV, 23, about 28 mm. long; the first segment is short, the 
following gradually increasing in length to the fifth and si.xth which are the lono-est, between 
one third and one half again as long as broad; the following segments very slowly decrease 
in length so that those in the distal third of the cirri are about as long as the distal diameter; 
in the distal third of the cirri the median portion of the distal dorsal edge of the segments 
is somewhat swollen, this on the last five or six before the penultimate becoming a blunt 
subterminal dorsal tubercle; the opposing spine is prominent, short, sharp, terminal, directed 
obliquely forward. 
The ends of the basal ravs are visible as laro-e rhombic tubercles in the angfles of the 
caly.K; the radials are entirely concealed; the IBr, are very short, broadly V-shaped with the 
pro.ximal and distal edges parallel; the lateral thirds of the proximal and distal edges are 
slightly produced; the axillaries are very short, nearly or quite three times as broad as long, 
rhombic in shape with concave sides and truncated lateral angles, the lateral edges being as 
long as those of the IBr^; the lateral edges and all but the median portion of the proximal edge 
are very slightly produced ; the synarthrial tubercles are low and broad, scarcely evident. 
The contour of the proximal portion of the animal is broadly rounded, as in C. 
sept en triotialis . 
The 26 arms are 125 mm. long; there are seven lIBr 4(3 + 4) and three IlBr 2 series; 
the IIIBr series are 2, internall\- developed except for one, which is situated by the side of an 
internal IIIBr series. 
