165 
pore, it is not until now that the species has been rediscovered. 
On the basis of the original description and the published figure 
I assigned this species to a place in the restricted genus Himer- 
ometra, chiefly on account of its large first pinnule (Pp or P,) and 
short brachials, no species of Heterometra in which the first 
pinnule is larger than the second being at the time known to 
me. I find, however, that I was wrong; the brachials are of the 
short wedge-shaped type characteristic of Heterometra, while the 
very irregular arm division is also unmistakable; neither are the 
joints of the division series swollen as is always the case in 
Himerometra. The proximal pinnules, though, for the genus, 
unique in their proportionate lengths, are of the type common to 
all species of Heterometra. 
Genus Pontiometra A. H. Clark. 
Pontiometra 1907. A. H. Clark, Smiths. Misc. Coll. (Quart. Issue), 
ol. 50, p. 354. 
Pontiometra andersoni (P. H. Carpenter). 
Antedon polypus Litken, M. S. 
Antedon andersoni 1889. P. H. Carpenter, Journ. Linn. Soc., (Z0ol.), 
NolL 21, p. 3067 pl. XXVI: mg 1—5; pl. XXVI, fig. 8. 
Pontiometra andersoni 1907. A. H. Clark, Smiths. Misc. Coll. (Quart. 
Issue), Vol. 50, p. 335. 
Singapore; April 20, 1906. One specimen with seventy- 
two arms 135 mm. long, cirri XXXVI, 75—78 (undeveloped cirri 
with 68—70), 70 mm. to 80 mm. long; first cirrus joint about 
three times as broad as long, the following slowly increasing in 
length to the thirteenth or fourteenth, which is squarish, then 
remaining the same, or becoming very slightly longer than broad, 
to the twenty-sixth or twenty-ninth (rarely as early as the twenty- 
third) which is squarish, mostly dark with a dull surface like the 
preceding, but becoming lighter and more polished distally, especi- 
ally on the dorsal side, like the succeeding; following joints at 
first very slightly broader than long, then gradually becoming 
shørter, the majority of the distal joints being about twice as 
