75 



undivided arms of the aclult. The longer proximal cirrus segments are half again as long as 

 broad, and are constricted' centrally, so that the cirri, which are rather slender, have very much 

 the appearance of the cirri of Stephanometra monacantha or of Dichrometra protectns. The 

 dorsal pole of the centrodorsal is slightly convex. 



2. Himerometra bartschi A. H. Clark. 



A. H. Clark. Smithsonian Miscellaneous Collections (Quarterly Issue), vol. 52, 1908, p, 212 



[Himerometra bartschi); p. 214 [H. persico). 

 Vidensk. Medd. fra den naturhist. Forening i Kobenhavn, 1909, p. 164 [Heterometra 



martensi). 



Proc. Biol. Soc. Washington, vol. 22, 1909, p. 7 [Himerometra bartschi, and H. persica, part). 



Crinoids of the Indian Ocean, 1912, p. 114 [Himerometra bartschi); p. 116 [H. persica; 



records from the Phiüppines). 



Stat. 96. Southeastern side of Pearl Bank, Sulu Archipelago. 15 fathoms. 1 Ex. 



This specimen has 61 arms 120 mm. long-, four of the rays bear 12 arms each, the 

 fifth 13; each IIBr series bears externally a IIIBr 4 (3 + 4) series, internally a IIIBr 2 series 

 which bears two IVBr 4 (3 + 4) series. 



The cirri are rather stout, 30 mm. long with i~] — 38 segments; the longest proximal 

 segments are from half again to twice as broad as long; there is very little difference between 

 the proximal and distal segments; from the nineteenth or twentieth segment onvvard prominent 

 dorsal tubercles or short blunt dorsal spines are developed. 



Pd is 23 mm. long with 37 segments, very stout basally but tapering evenly to a slender 

 and flagellate tip, the basal segments are twice as broad as long, the following gradually 

 increasing in length and becoming about as long as broad on the tvvelfth, and half again as 

 long as broad in the delicate terminal portion ; the pinnule is perfectly smooth, with no tracé 

 of eversion of the distal edges of the segments. Pp is 22 mm. long with 36 segments, only 

 very slightly smaller than Pd- Pj is similar to the two preceding but somewhat smaller, 1 7 mm. 

 long. P„ is weak and slender, 8.5 mm. long with 23 segments of which the second-fifth have 

 a prominent narrow carination the distal border of which is parallel to the longitudinal axis of 

 the segments. P 3 is 6.5 mm. in length, resembling P 3 but very slightly smaller. P t is 5.5 mm. 

 long, resembling P 3 but very slightly smaller-, the second-fourth segments are carinate. From 

 this point the amount of carination of the earlier segments of the pinnules decreases, though 

 it is traceable to the end of the proximal fourth of the arm. 



This specimen differs from the type specimen only in the slightly smaller size and in the 

 slightly shorter proximal cirrus segments. 



Heterometra A. H. Clark. 

 Key to the Species of the Genus Heterometra. 



a 1 Enlarged proximal pinnules without prominent keels on their earlier segments 

 b 1 enlarged proximal pinnules smooth, slender, the component segments 

 without lateral processes or produced and spinous distal edges 



