128 
The Copenhagen collection has been of great importance to 
me in making clear the relationships of the comatulid fauna of 
the Mediterranean Sea and the coasts of western Europe. Two 
genera are found in this region, Antedon and Leptometra, the 
former littoral and sub-littoral, the latter inhabiting rather deep 
water. No close relative to the former was known until Mastig- 
ometra was described, based upon a single specimen, the type of 
M. flagellifera, in this collection. Now Mastigometra is very closely 
related to Antedon, differing chiefly in the greater length of the 
pinnules following P,. Mastigometra flagellifera was without data 
as to locality; but later I found in the ,,Investigator" collections 
a second species, MM. micropoda, differing from M. flagellifera in 
much the same way that Antedon petasus differs from A. mediter- 
ranea, which inhabits the Indian Ocean, some of the specimens 
having been taken at Ceylon. Antedon, then, is most closely 
related to, and undoubtedly a derivative from, an Indo-Pacific type. 
Leptometra is peculiar in the great length and similarity of P4 
and P,, and in the regular arrangement of the cirrus sockets, 
thereby differing from all other genera of the Antedonidæ except 
Zenometra and Psathyrometra.  Moreover, the great size of its 
cirri also suggests a relationship to these two genera. The absence 
of the spines on the calyx and of the strong lateral flattening 
of the I Br series and lower brachials, as well as the compara- 
tively long distal cirrus joints, indicate that Psathyrometra is its 
closest relative. The species of Psathyrometra with which I was 
previously acquainted are all large, robust forms; but the ,,Investi- 
gator" collection contained two new species from the Indian Ocean 
peculiar in being of very delicate build, and, therefore, much like 
cirra"), as occurring in ,Peru", and both of them appear to have 
considered this to be the South American country of that name. This 
record has puzzled me a great deal, as it is totally unsupported by 
other records: but I believe the ,Peru" meant must be the Peru 
(or Francis Island) situated in about 1930' E lat., 1769 E. long., in 
the Gilbert or Kingsmill group. This species bas been recorded by 
Carpenter from these islands, though ae indbo any definite island. 
