i8 5 



2. Pachv lomctra sclateri (Bell). 



Bell. Marine Investigations in South Africa, vol. 4, 1905, p. 140, pi. 3, figs. 1 — 3 {Antedon 



sclateri). 

 A. H. Clark. Smithsonian Miscellaneous Collections, vol. 61, 1 9 1 3, N° 15, p. 48 {Pachylo- 



metra sclateri). 



3. Pachylometra distincta (P. H. Carpenter). 



P. H. Carpenter. "Challenger" Reports. Comatulae, 1888, p. 247, pi. 51, fig. 1 {Antedon 



distincta). 

 A. H. Clark. Smithsonian Miscellaneous Collections (Quarterly Issue), vol. 52, 1908, part 2, 



p. 227 {Charitometra smithi). 

 Proc. U. S. National Museum, vol. 39, 191 1, p. 555 {Pachylometra distincta); p. 557 



{Pacl/ y lometra smithi). 

 Smithsonian Miscellaneous Collections, vol. 61, 1913, N° 15, p. 48 {Pachylometra distincta). 



4. Pachylometra levigata A. H. Clark. 



A. H. CLARK. Proc. U.S. National Museum, vol. 36, 1909, p. 406 {Pachylometra levigata). 



Monachometra A. H. Clark. 

 There is only one species in the genus Monachometra. 

 1. Monachometra fragilis (A. H. Clark). 



A. H. CLARK. Proc. Biol. Soc. Washington, vol. 25, [912, p. 79 {Pachylometra fragilis). 



Stat. 166. 2°28'.sS., i3i°3'.3E. Halmahera Sea. 118 Metres. 1 Ex. 



The centrodorsal is low, flattened hemispherical, 7 mm. in basal diameter and 3 mm. 

 high; the cirri are closely crowded, arranged in tvvo or three irregular rows and approximately 

 fifteen columns, three in each radial area ; the cirrus sockets in the proximal row reach the 

 proximal border of the centrodorsal. The centrodorsal in general resembles that of the species 

 of Crinomeira. 



The cirri are about XXX, 17 — iS, 30 mm. to 35 mm. long, moderately slender; the 

 first four segments are short, the fifth half again as long as broad, the sixth, seventh and 

 eight twice as long as broad, the following gradually decreasing so that the distal are about 

 as long as broad, and the terminal increasing again so that the penultimate and antepenulti- 

 mate are about twice as long as broad; the longer proximal segments have slightly prominent 

 ends, while the shorter distal have the dorsal distal margin slightly swollen. 



Deep, but very narrow, subradial clefts are present. 



The ends of the basal rays are large and prominent, forming rhombic areas in the 

 angles of the calyx. 



The radials are very short, strongly curved, with a low, broad and obscure median tubercle. 



The IBr x are exteriorly very short, band-like, with an obscure low median tubercle ; 

 inwardly they are produced toward the centre of the calyx so that their sharply flatened 



SIBOGA-EXPEDITIE XLU*. 24 



