A MONOGRAPH OF THE EXISTING CRINOIDS 353 



which the first is rounded wedge-shaped with the narrower end directed proximally 

 and the broader end overlapping the entire lateral border of the hypozygal; it is thus 

 somewhat broader than the length of the second brachial; the second segment is 

 greatly expanded, but not so broad as the first; the following sogments are subequal, 

 about one third as broad as the second, and about as long as broad. Pj 10 mm. or 

 11 mm. long, stifY and spinclike, though comparatively slender, composed of 25 

 segments of which the first 2 are much enlarged as in P,, the third is about as long as 

 broad, and those following become progressively elongated, being distally about twice 

 as long as broad. P3 is 13 mm. long, and resembles P2 but the segments are more 

 elongate and the distal have somewhat overlapping and finely spinous ends. P4 is 

 similar to P3, but 11 mm. long like P2. 



The following pinnules decrease in length to P,, wliich is 7 mm. long with 15 

 segments of which the first 2 are very broad and the remainder are about twice as long 

 as broad, then gradually increase in length reaching 11 mm. distally. The first three 

 pinnules are rounded styliform, those succeeding more sharply styliform and slightly 

 stouter, remaining so until the end of the arm. The terminal pinnules extend 4.5 mm. 

 beyond the tip of the arm. The enormous expansion of the first 2 pinnule segments is 

 most noticeable on the weak and slender Pi ; it is of the same size absolutely, though 

 relatively less, on the somewhat stouter succeeding pinnules. After P4 it becomes 

 absolutely smaller, and from that point onward the first segment is very short, about 

 half again as broad as the third, and the second is short and intermediate between the 

 first and third. 



Notes. — The two known specimens of this form were originally considered as rep- 

 resenting different species distinguished by the presence or absence of anterior inter- 

 radial extensions of the radials. In the type of versicolor the radials are interradially 

 produced upward in the form of a very narrow interradial process over the distal end of 

 which the IBr, meet, and the larger part of the IBr, and the IBr2 are widely separated 

 laterally. In the type of propinqua the radials appear externally as small interradial 

 triangles with no distal processes and the IBr, are in apposition for their entire lateral 

 edges, though the IBrj are widely separated. 



Further study showed that the condition of the interradial portion of the radials 

 is variable in each individual, and certain interradial areas in one are quite similar to 

 interradial areas in the other. A study of a very much larger series of Neometra 

 multicolor than was available at the time the original descriptions were written has 

 led me to regard the presence or absence of anterior prolongations of the radials in 

 the interradial angles as a minor varietal rather than as a specific character. 



In the type of versicolor the cirri are XX-XXV, 45, 23 mm. long, with the longest 

 segments about as long as broad. The 20 arms are 90 mm. long, and are composed 

 of 130 brachials. Pi is 7 mm. long with 30 segments. P2 is 10 mm. long, stiff and 

 spinelike, with 25 segments. P3 is 13 nim.Mong,fresemblingjP2. P^ is similar but 

 slightly shorter. Pj is 7 mm. long with 15 segments. 



In the type of propinqua the cirri are XXV, 45, 25 mm. long, with the segments in 

 the basal half ratlier longer than broad. The 20 arms are 70 mm. long with about 120 

 brachials. P, has 20 segments. P2 is much longer and stouter, stiff and rodlikc, 

 with about 15 segments. P3 is even longer and stiff er, after which the pinnules de- 

 crease to about Pg, thence increase very slightly distally. 



