PART 5 A MONOGRAPH OF THE EXISTING CRINOIDS 753 



Description. The centrodorsal is hemispherical, with a small bare dorsal pole. 



The cirri are about XXX, about 10, approximately 6 mm. long. The first segment 

 is very short, the second is somewhat longer than broad, the third is about four times 

 as long as the proximal breadth, and the fourth and fifth, which are the longest, are 

 nearly or quite six times as long as the proximal breadth with expanded and overlapping 

 very finely spinous distal ends. The following segments slowly decrease in length so 

 that the third from the terminal claw is three times as long as broad, the antepenultimate 

 is twice as long as broad, and the penultimate is from half again to twice as long as 

 the distal width. The opposing spine is represented by a small terminal tubercle. 

 The terminal claw is moderately slender and rather feebly curved. 



The radials project slightly beyond the rim of the centrodorsal. The IBr : are 

 very short, about four times as broad as the lateral length, deeply incised in the median 

 line by a posterior process from the IBr 2 , not in contact basally, and bear tufts of fine 

 spines on the anterolateral angles which are continued inward, decreasing in size, along 

 the distal border. The IBr 2 (axillaries) are broader than long, with all the sides strongly 

 concave and the anterior and lateral angles strongly produced; a prominent rounded 

 posterior process incises the IBri; the lateral angles are armed with short but prominent 

 spines; the anterior edges are slightly everted and are armed with fine spines. The 

 anterolateral angles of the IBrj are more or less cut away, leaving a V-shaped notch 

 in the sides of the IBr series. The sides of the IBr series and of the first two brachials 

 are flattened, but are not in apposition. 



The 10 arms are about 15 mm. long. The first brachials are about three times as 

 long exteriorly as interiorly, and are deeply incised by the second ; the inner edges are 

 entirely free, diverging from each other at an angle of about 60; the outer border is 

 straight, with a broad band of very fine spines. The second brachials are much larger, 

 irregularly quadrate. The first syzygial pair (composed of brachials 3+4) is longer 

 interiorly than exteriorly, and about as broad as long in the median line. The next 

 four brachials are almost triangular, about as long as broad or slightly longer than broad, 

 those following becoming somewhat less oblique and longer distally. The distal edges 

 of the brachials are produced and armed with prominent, though fine, spines. 



Syzygies occur between brachials 3+4, 9 + 10, and 16+17. 



P! has the first segment short, the second longer, the third twice as long as broad, 

 and the following much elongated with expanded and spinous distal edges. P 2 is 

 somewhat longer and stouter than P, with longer segments of which the third to fifth 

 bear a fusiform gonad. The following pinnules resemble P 2 . 



Localities. Ingolf station 36; southwest of Godthaab, Greenland (lat. 6150' 

 N., long. 5621' W.) ; 2623 meters; temperature 1.5 C. [A. H. Clark, 1923] (1, U.S.N.M., 

 E. 1069). 



Ingolf station 11; west of Faxafjord, Iceland (lat. 6434' N., long. 3112' W.); 

 2376 meters; temperature 1.6 C. [A. H. Clark, 1923] (1, C.M.). 



Ingolf station 18; southwest of Iceland (lat, 6144' N., long. 3029' W.); 2075 

 meters; temperature 3.0 C. [A. H. Clark, 1923] (1, C.M.). Type locality. 



Geographical range. Extreme northwestern Atlantic, from Baffins Bay to Iceland. 



Bathy metrical range. From 2075 to 2623 meters; the' average of 3 records is 2358 

 meters. 



Thermal range. From 1.5 C. to 3.0 C.; the average of 3 records is 2.0 C. 



