A MONOGRAPH OF THE EXISTING CRINOIDS 105 



The IBfi are three times as long as broad, and are basally separated laterally by 

 the anterolateral angles of the radials. The IBr2 (axillaries) are low pentagonal, three 

 times as broad as long, Avith the anterior angle obtuse. The articulation between the 

 elements of the IBr series is close, and there is a slight synarthrial tubercle. 



The first 2 brachials are closely united laterally. The first 6 brachials are short 

 and discoidal, but the ends of those following become oblique. The distal edges of 

 the outer brachials are much everted and finely spinous. The distal intersyzygial 

 interval is 4-6 muscular articulations. 



The first 5 pinnules bear combs. Pi is 6.5 mm. long with 32 segments, of which 

 18 bear teeth. P2 is 5 mm. long with 31 segments, of which 18 bear teeth. P3 is 

 4 mm. long with 24 segments, of which 15 bear teeth. P4 is similar to P3. Ps is 

 3.5 mm. long with 24 segments, of which 14 bear teeth. The distal pinnules are 

 4.5 mm. long with about 17 segments, of which the distal bear dorsal hooks. 



The mouth and anal tube are subceutral. The color m alcohol is yellow brown 

 with white spots; the cirri are white. 



In the specimen from station 43 the cirri are XVIII, 14-17, from 6 to 10 mm. in 

 length. Dorsal spines are developed from the sixth segment onward. 



There are 12 arms 55 mm. in length. The distal intersyzygial interval is 3 or 4 

 muscular articulations. 



Pi and P2 have long combs composed of 15-20 teeth. Pi is 5.5 mm. long, and 

 P2 is 4.5 mm. long. P5 is 3 mm. long, its comb with about 10 teeth. Pj has no comb. 

 The distal pinnules are 4 mm. long with 13 segments. 



The disk is 4 or 5 mm. in diameter; the mouth and anus are subcentral. 



The color is brownish green, the skeleton lighter, olive brown. 



Doctor Gislen remarks that the young individuals of C. stelligera and C. maculata 

 are very similar and probably can not be distinguished from each other. He says 

 that presumably they pass through a stage in which the cu-ri are formed like those 

 of C. brachycirra. 



The specimen in the Australian Museum labeled "Port Jackson" has 36 arms, 

 which were origmally about 90 mm. long. The cirri are XXII, 18-20, 20 mm. long. 

 The eversion of the distal edges of the brachials is especially well marked, and there 

 is an indication of an eversion of the distal edges of the elements of the division series. 



Abnormalities. — In one of the specimens secured by the Challenger there are 

 2 mouths and 2 anal tubes. The true mouth is interradial, and there is a large 

 subcentral anal tube immediately behind it. But there is also a second anal tube 

 occupying the interval between the posterior ambulacrum which curves around the 

 left-hand portion of the disk and the branches of the lateral ambulacrum on its 

 right-hand side. This is very irregular in character, and at one portion of its course 

 expands into a second peristome in which there is a small mouth. The figure of the 

 disk of this specmien published by Carpenter in 1880 was republished in 1884. 



Carpenter noticed that the arrangement of the ambulacra in one of the speci- 

 mens collected by Dr. John Anderson in the Mergui Archipelago is very singidar. 

 The mouth seems to be radial, and the number of groove trunks connected with the 

 peristome is very considerable. The aboral portion of the left anterolateral ray, 



