138 



THE VOYAGE OF H.M.S. CHALLENGER. 



;iad most of the Pcntacrinidse, have as yet been obtained at one or two localities only, 

 and those not very widely separated. 



T.ible IT. on the preceding page gives the bathymetrical and geographical ranges, so far 

 as yet known, of all the genera of recent Crinoids ; their distribution in the various oceans 

 beii3g indicated by the capital letters in the fourth column. A few cases of uncertainty, 

 owing to deficiency of information and other causes, are noted under t!:e head of remarks. 



B. Bathymetrical Eange. 



Tlie frequency of occurrence of all the genera of recent Crinoids at depths below 250 

 fathoms, so far as has yet been made known, is shown in Table III. One or two curious 



Table III. — Showing the Frequency of Occurrence of all the Genera of Recent Crinoids 



at dejyths heloiv 250 fathoms. 



Genus. 



PcTitacrinus, . 



Metacrinus, 

 Ehizoeriims, . 



' ithycrinus, . 

 flyocrimis, 



Holopus, 



Antedon, 

 Adinomeira, . 



Etuliocrinus, . 



Promachocrinus, 



Atelecrinus, 



Tlmumatocrinus, 



200-500 f. 500-7001 



1 



10 



56 

 5 



1? 



700-1200 f. 1200-2000 f. 



2000-2500 f. 



1 



1? 



2500-2900 f. 



Remarks. 



Only four of the seven dreilgings 

 noted in the first column were at 

 a gieater depth than 250 fath. 



A stem-fragment only at St. 323; 

 1900 fath. Lat. 35° 39' S. {fido 

 C.W.T.). 



Possibly a young specimen from St. 

 223, in N.W. Pacific, 2325 fath. 

 ijidc C.W.T.). 



{ Ai tlireo of the Stations recorded in 

 \i!c first column (for each genus) 

 the depth was between 200 and 

 230 fath. Stations 174b, c, d 

 {•2iZ. SIO ind 210 fath.) are not 

 i rs;- r either genus, 



I 0. ■■■',! information. 



Lowest limit (station 174C; 610 

 lath.) uncertain. Possibly not 

 below 450 fath. 



contrasts are noteworthy. While Bathycrimis and Hyociinus are essentially abyssal 

 forms, Actinometra is not known with certainty to occur below 533 fathoms, and has 

 not been obtained more than seven times below 200 fathoms.^ Pentacrinus, having a 



1 Comatulse were dredged at Stations 174b, 174c, 174d, the deirths being resi^eutiyely 235, 610, and 210 fathoms ; 

 but there is no record of the particular haul which yielded the Comatula'. 



