[10 



following pinnules gradually decrease in size, then increasing in length and becoming very 

 slender distall)-. 



The colour is white, with a faint median line of light pinkish in the proximal half of 

 the arms. 



3. Mariametra tenuipes \. 11. Clark. 



\. 11. Clark. Ann. and Mag. \.it. Hist., series 8, vol. io, 1012, p. 32. 

 St.it. 294. ioijjS., 124 .•;.;i:. 73 Metres. 1 Ex. 



The dorsal pole of the centrodorsal is slightly convex, 1 mm. in diameter, covered with 

 smal! tubercles. 



The cirri are XXVI, 24 — 20, 2: mm. long; the firsl segment i s short, the second about 

 twice as broad as the median length, the third slightly longer than broad to half again as 

 long as broad; the sixth-eighth are about three times as long as the median diameter; the 

 following gradually decrease in length so that the last ten or eleven are about as long as 

 their distal diameter, or only very slightly longer; the cirri are exceedingly slender; the long 

 proximal segments have slightly prominent ends; slight subterminal dorsal spines appear on 

 about the eleventh segment. 



The division series and arms in general resemble those of the other species of the 

 genus. One IIIBr series is present, external. 



The 15 arms are probably about 45 mm. long. 



The lateral ornamentation of the division series, which occupies the outer third of the 

 exposed surface of the elements of the IHr series thence narrowing distally and disappearing 

 at the base of P,, consists of very numerous small blunt spines, more or less coalescent, which 

 show a tendency to become arranged in horizontal rows. 



1', is 6 mm. long with about 16 segments, small and short. P a is 7.5 mm. long with 

 19 segments, resemblin^ 1' ; but not so stout, though slightly stouter than P r P.. is 1 1 mm. 

 long with 21 segments, slender, evenly tapering; the first segment is not ciuite so long as 

 broad. the second is about as long as broad, and the fifth and following are about twice as 

 long as broad, becoming more elongated terminally. \\ is 9 mm. long with 19 segments, 

 resemblin- I' 



The colour is white with a narrow median line on the division series and arms of 

 purple; the cirri are light purplish. 



VI. Familj C idai .\. 11. Clark. 



Key to the Genera ol the Family Colobometridaë. 



a' I', (the first inner pinnule) present on all the arms 



more than 10 arms; size medium or large; cirrus segments subequal, 

 short, bearing dorsally paired spines or tubercles; P greatly enlarged, 



