REPORT ON THE CRINOIDEA. 361 



Stem slender and pentagonal in outline, with .slight re-entering angles. Generally 

 seven or eight interuodal joints with distinctly crenulated edges. Their relatively high 

 sides are somewhat hollowed, and smooth or marked with foint ridges ; while their angles 

 are sharpened and a little produced outwards, so that the whole stem is traversed by five 

 well defined interradial ridges. 



The supra-nodals are but slightly incised, and the wide cirrus-facets do not reach the 

 upper edges of the nodal joints. They likemse barely reach the lower edges, coming 

 much nearer to them in some specimens than in others ; and the infra-nodals are scarcely 

 grooved, so that their re-entering angles are but little more marked than those of the 

 other internodal joints. 



Cirri composed of about forty joints, the first two of which are short and wide, while 

 the eighth and a few following ones are sometimes a little longer than wide. The lower 

 cirri do not seem to be specially shorter than the upper. Interarticular pores not 

 visible below the tenth node. 



The basals (in the only specimen possessing them) appear as small rhomboidal knobs 

 with their pointed lower extremities resting on the interradial ridges at the top of the 

 stem ; but they extend laterally and meet their fellows in the re-entering angles between 

 the first radials. The rays consist of six rounded joints, of which the second and fourth 

 are sj^zygies, and are well separated laterally above the hypozygals of the second radials. 

 They all divide three times, and there are generally additional axillaries on the two outer- 

 most of each set of four tertiary arms thus produced, so that the total number of arms 

 reaches about sixty. They consist of about one hundred joints above the palmar 

 axillaries, and are almost smooth in the medio-dorsal line till near the ends, which are 

 slightly serrate. 



The distichals, palmars, and lower brachials present a peculiarity which is much more 

 marked in the baseless individual than in the more normal one. The pinnule-bearing 

 side of each joint is slightly bent outwards above the pinnule-socket, and its edge is cut 

 into several small teeth or spines. In addition to this the front edge of each joint and 

 the coiTesponding part of the hinder edge of its successor are slightly raised on one or 

 both sides, and are also more or less spinose. These characters are perhaps most distinctly 

 marked upon the palmars, not being fully developed upon the distichals, and disappearing 

 a little beyond the level of the tertiary axillaries. Six or eight joints in the primary 

 arms ; secondaries of eight to fourteen (usiially ten or tAvelve) palmars. The next division 

 (when present) may be from eight to twenty (generally twelve to sixteen) joints, and in 

 one case there is another axillary after sixteen joints more. The third joint after each 

 axillary is usually a syzygy. The next syzygy in the free arms may be anywhere 

 between the sixth and thirtieth brachials, after which an interval of three to eighteen 

 joints occurs between successive syzygies. 



The pinnules on the radials and first distichals are large and massive, consisting of 



(ZOOL. CHALL. ESP. — PAET XXXII. — 1884.) li 46 



