A MONOGRAPH OF THE EXISTING CRINOIDS 687 



The radials are seven times as broad as long. The IBr, are three times as broad 

 as long and are laterally free; they form a weak synarthrial tubercle with the axillary, 

 which is twice as broad as long witli somewhat concave distal sides. 



The 10 arms, which arc all broken, are 15+ mm. in length. The first brachials 

 are interiorly united for two-thirds of their length. The arm bases are tolerably 

 smooth; after the seventh brachial the distal edges are slightly everted and spiny. 

 The width of the arms proximally is from 0.6 to 0.8 mm. 



Syzygies occur between brachials 3 + 4, 11 + 12, and lG + 17, and distally at 

 intervals of 4 muscular articulations. 



P, is 5.5 mm. long and is composed of 27 segments. The comb is made up of 

 9-11 rather low triangular teeth which in height equal three-quarters the width of 

 the segments. Pj is 3 mm. long and bears a comb of 6 teeth. P3 bears a rudimentary 

 comb, and P4 is without a comb; the last is 1.5 mm. long and is composed of 11 

 segments. 



The disk is 4 mm. in diameter, and is smooth without papillae. The mouth is 

 somewhat displaced marginally. The anal tube is subcentral, chimney shaped, 1.5 

 mm. high. 



Another specimen has the cirri XIX, 9-12, from 2 to 4.5 mm. long. The basals 

 are visible in the interradial angles. The radials are five times as broad as long. The 

 distal edges of the axillaries are everted and spiny. The 10 arms are 25 mm. long. 

 The distal brachials are twice as long as broad and are strongly constricted centrally 

 and spiny. Syzygies occur between brachials 3 + 4 and 11 + 12 and distally at 

 intervals of usually 3 muscular articulations. 



Pi is 3 mm. long with about 20 segments and bears a comb of about 5 coarse 

 teeth. P2 is absent. P3 is 1.5 mm. long with 7 segments and is without a comb. 



The disk is 2.5 mm. in diameter. The mouth is somewhat displaced. The anal 

 funnel is 1 mm. high. 



Gisl^n remarks that it is doubtful if this last individual belongs to the genus 

 Comantheria. 



YOUNG INDIVIDUAL OF A SPECIES OF COMANTHUS (COMANTHUS) 



Locality. — Chio-ta-jima; shore at low tide; August 3, 1914. 



Azotes. — The cirri are XII, 9, from 2 to 3 mm. long, slender, in a single row. The 

 fourth segment is the longest — twice as long as broad. The ccntrodorsal is low and 

 flattened. 



The radials are narrow bands, five times as broad as long. The IBri are twice as 

 broad as long and are laterally free. The IBr2 (axillaries) are half again as broad as 

 long, pentagonal. 



The 10 arms are 12 mm. long. The first brachials are well sejjarated interiorly. 

 The synarthry between the first and second brachials is usually rather similar to the 

 syzygy between brachials 3 + 4. The first and second brachials are three times as 

 broad as long, somewhat longer exteriorly than interiorly. The brachials are serrate 

 and only slightly overlapping. 



The intersyzygial interval is 3 muscular articulations. 



Pi has a comb consisting of about C teeth. 1% and P3 are rudimentary or lacking. 

 The following pinnules are without a comb. The distal pinnules are 2.5 mm. long. 



