58 THE ECHINODERMS OF TORRES STRAIT. 
statement that there are a few entrenched pedicellariz on the marginal plates. He does 
not mention the size of his specimen, so one can not determine whether the pedicellarize 
may be associated with youth, as is apparently true in some sea-stars. Quite small speci- 
mens of this species were described by Perrier as a new species of Fromia, although they 
had no actinal papule. The only known localities for canariensis are in the Canary and 
Cape Verde Islands. The largest specimen has R =115 mm. 
Narcissia trigonaria. 
Sladen. 1889. Challenger Ast., p. 414; pl. Ixv, figs. 5-8. 
The type of this species with R =62 and r=13 mm. was taken near Bahia, Brazil. 
A species of Narcissia was taken by the Albatross, February 7, 1885, in 25 fathoms on the 
fishing banks south of Cape San Blas, Florida. Verrill (1915, p. 98) refers these 
specimens to Sladen’s species. One of them is in the Museum of Comparative Zodlogy 
collection. It differs from trigonaria, however, in the absence of tubercles on the abactinal 
median plates of the basal part of the rays. These plates are scarcely at all swollen or 
enlarged and the rays are not carinate, but these peculiarities may be due to youth, as R 
is less than 40 mm. Sladen’s figure shows about 13 irregular series of abactinal plates 
on each ray, while there are only about 9 on the Florida specimen. The latter has narrow, 
entrenched pedicellarize on some of the basal superomarginal and abactinal plates, whereas 
Sladen makes no reference to such organs in the type. The madreporic body is elliptical 
in the Florida specimen and subtriangular in the one from Brazil. These differences are 
all well within the probable limits of growth-change and individual diversity. 
FERDINA. 
Gray. 1840. Ann. Mag. Nat. Hist., 6, p. 282. 
Genotype: Ferdina flavescens Gray, l. c. Type designated by Fisher, 1919. 
This genus is relatively little known and few species have been assigned to it. Besides 
the type species, Gray included a second form, F’. cwmingii, of which Perrier subsequently 
(1875) gave an adequate description. Sladen (1889) added the Scytaster kuhlii of Miller 
and Troschel and the Scytaster cancellatus of Grube. No further additions to the genus 
were made for twenty years, when Koehler described F. offreti.. Finally in 1913 Fisher 
added a species from Celebes, F’. glyptodisca. At Mer, I found a single specimen of a beau- 
tiful species allied to these but apparently distinct. There are, then, 7 species to be recog- 
nized in the genus, but 5 of these are known from only 1 specimen each (or at most 2), 
while one of the others is known only from the original dry specimens, which have been 
in the British Museum for more than 75 years. It is obvious, then, that it is still open to 
question whether the 7 species are all valid and congeneric. It seems to me quite possible 
Key to the Species of Ferdina. 
No marginal or abactinal plates bare. 
Abactinal plates relatively few, large, convex; two series of actinolateral plates................... flavescens 
Abactinal plates more numerous and mostly smaller, but some strongly convex, tubercle-like; only 
onesseriesiofactinolateralplatesten.c: coc ce stro carotene ees cites Nee AEE eee eee cumingit 
Some marginal and abactinal plates conspicuously convex and bare. 
Rays short and wide, R=3-3.5 r. 
Superomarginal plates in fairly regular series on each side of ray. 
Adambulacral spines, 2; granules at center of abactinal plates larger than around margins. offreti 
Adambulacral spines, 3; granules at center of abactinal plates smaller than around margins glyptodisca. 
Superomarginal plates in irregularly alternating series of large and small plates. 
5 or 6 transverse series of small but conspicuous, convex, bare plates on abactinal surface 
of each ray, corresponding in position to smaller superomarginal plates.............. cancellata 
No transverse series of bare abactinal plates but 2 to 4 such plates occur on distal half of 
ORCI Y rece sara ees eecc coe STO ERS hee Tels toss 8, ote ono SRC REO eee ocellata 
Raysilongiandinarrow; (RiSHoSns wanders Sh A RNs I ee oe kuhlit 
