ANNOTATED LIST. 19 
Comanthus parvicirra. 
Alecto parvicirra J. Miller. 1841. Arch. f. Naturg., 7, p. 145. 
Actinometra parvicirra P. H, Carpenter. 1888. Challenger Comat., p. 338, pl. Ixvii, figs. 3, 4. 
Comanthus parvicirra A. H. Clark. 1908. Smithson. Mise. Coll., 52, p. 203. 
(Plate 1, Figures 5 and 7.) 
This is the most perplexing comatulid found at Mer, for while typical specimens are 
easily recognized, the intergradations with annulata are very puzzling. Moreover, the indi- 
viduals which seem to be undoubtedly parvicirra differ so among themselves that it is hard 
to believe they represent a single species. This is well shown on plate 1, where figure 5 
represents an arm of a red and white form and figure 7 represents the arm of a very different- 
appearing grayish form. It will be noted at once that not only in color but in the shape 
of the arm the differences are very great. The preserved specimens look less unlike each 
other and a careful comparison fails to show any good reason why they should not both 
be called parvicirra. It will be observed that the grayish individuals have the arm-segments 
yellow-brown with the joints and the pinnules purplish-brown, but the general effect both 
in life and in alcohol is gray. One of the most strikingly colored individuals seen was 
greenish-yellow and rich red-purple, while another had the basal half of the arms red and 
white (as in pl. 1, fig. 5) with the distal half bright-greenish-yellow. It is evident, there- 
fore, that little reliance can be placed on color to help in distinguishing parvicirra, yet it 
is certain that very dark-colored specimens were not noted at Mer and, except for the 
grayish specimens, bright colors were the rule. The shade of red in the red and white indi- 
viduals is elusive, for while in bright sunlight it seems to be almost rose-red, with less illu- 
mination it is more a dull blood-red and in shade it becomes almost a light liver-brown. It 
is quite fugitive in alcohol, the specimen becoming more or less light brown. Aside from 
the matter of color, parvicirra is distinguishable from annulata by its lighter, more fragile 
structure, the presence of some cirri, and the relatively small number of arms. As many 
specimens of annulata, however, have only 21 to 29 arms and often have cirri, sometimes 
18 or 19, it is only by a careful weighing of all the characters that the two species can be 
distinguished. I am by no means sure that they really ought to be regarded as distinct, 
but on the other hand it seems to me unwise to include them under a single name. Perhaps 
further observations on living specimens may reveal a more natural line of division than 
is at present known. There is little danger of confusing parvicirra with luteofusca, the 
former has so much longer and more slender arms, fewer and shorter cirri, and lacks, more- 
over, the characteristic coloration of luteofusca. 
There are records of parvicirra from the Seychelles on the west to the Tonga Islands 
and Samoa on the east; northward it is said to reach southern Japan, while southward it 
extends at least as far as Port Molle, Queensland. Whether all the records really refer to 
parvicirra seems to me open to question. For example, I think there is little doubt that 
Reichensperger’s record from the Aru Islands (1914, p. 89) refers to a specimen of annulata. 
Comanthus samoana. 
A. H. Clark. 1909. Proc. U.S. Nat. Mus., 37, p. 30. 
(Plate 20, Figure 4.) 
This species was found with annulata and parvicirra on the reefs at Mer, but so incon- 
spicuous are its specific characters that not until the specimens of Comanthus collected in 
Torres Strait were being sorted at Cambridge was its occurrence there discovered. Eight 
specimens were found at the Murray Islands and a ninth subsequently at Badu. ‘The 
species is now known from the Bay of Bengal eastward to Samoa and south to New Cale- 
donia, but it has not yet been found west or southwest of New Guinea. (For a discussion 
of the relationship between samoana and luteofusca, see antea, p. 18.) 
