'45 
2. Pteroiiietra piilchcrrinia (A. H. Clark). 
A. H. Cl.ARK. Froc. U. S. National Museum, vol. 36, 1909, p. 400 (Ptiloinetra pulcherrima). 
Proc. U.S. National Museum, vol. 39, 191 1, p. 547 {Asterometra pulcherrima). 
Crinoids of the Indian Ocean, 19 12, p. 193 [AsUroinetra pulclierrima). 
Stat. 144. Anchorage north of Salomakiec (Damar) Island. 45 Metres, i Ex. 
This specimen agrees well with the type. There are twenty arms 90 mm. to 95 mm. 
loni;-. The cirri are XX, 92 — 96, "I'i mm. lung. The colour in alcohol is white. 
2"'^ Subfamily 1" h al ass o m e t r i n a e A. H. Clark. 
Key to the Genera of the Subfamil)' Thalassometrinae. 
a' Ten arms 
b^ genital pinnules with the thinl-fifth segments greatly expanded, forming 
a broad roof over the gonads ; calyx and arm bases smooth ; 30 — 40 
cirrus segments (Straits of F" 1 o r i d a and southeastward to 
Grenada) Horaeometra 
b" no expansion of the segments of the genital pinnules 
c' ossicles of the division series and of the arm bases with numerous 
prominent spines which may be more or less confined to the borders 
of the ossicles and to the median line, or generally distributed over 
the dorsal surface ; ossicles of the division series and first two brachials 
sometimes with a slight carinate process bearing spines along the 
crest; arms beyond the second brachial well rounded dorsally, never 
carinate; Pj very stout, much stouter than the succeeding pinnules, 
though with a delicate tip; 10 — 13 (usually 10) arms; division series 
usually 2, sometimes 4 (3 -|- 4) (M or occo and Madeira south- 
ward to Ascension and the Crozet Islands; east Africa 
to the Kermadec, Galapagos, Hawaiian and western 
Aleutian Islands, and southern Japan) Thalassometra 
c'- ossicles of the division series and of the arm bases smooth, without 
spines on the dorsal surface, though they may have irregular processes 
on their lateral borders, and isolated spines on their proximal and 
distal borders; Pj, though larger and stouter than those succeeding, 
is not especially enlarged 
d^ cirri long, with more than 40 segments 
e^ division series and arms very narrow and strongly compressed 
laterally; a prominent narrow, usually low, keel runs the entire 
length of the division series and arms; the lateral borders of 
the ossicles of the division series and of the arm bases bear 
coarse irregular spines; the proximal cirrus segments have a 
SIBOGA-E.XPEDITIE XI.ll/'. '9 
