242 13ULLETIN 76, UNITED STATES NATIONAL MUSEUM. 



Genus LINCKIA Nardo. 



Lin[c]kia Naudo, Okon's Isis, 1834, p. 717. Typo, L. typiis (by (ipsignation) =L. Isevigata 

 (Linnffius).— Ghay, Ann. and Mag. Nat. Hist., vol. 6, Dec, 1840, p. 234. 



Cribrdla Aoassiz, M^m. soc. sci. nat. Neuchatel, vol. 1, 1835, p. 191. 



OphidiasUr (part) Mulleh and Troschsel, Monatsber. preuss. Akad. Wiss. Berlin, April, 1840, 

 p. 103. 



Acalia Gray (subgenus), Ann. and Mag. Nat. Hist., vol. (i, 1840, p. 285. 



Diagnosis. — Linckiidse with small disk and long cylindrical arms; abactinal 

 plates irregularly disposed, not in regular longitudinal series"; papulre in areas, 

 irregularly scattered, except between the marginal plates; no actinal papulae; no 

 pedicellarisc; adambulacral armature granuliform in two series. 



LINCKIA COLUMBIA Gray. 

 PI. 48, figs. 1-7. 



Linckia cohimbim Gray, Ann. and Mag. Nat. Hist., vol. 6, 1840, p. 285; Synopsis, 1866, p. 14.— 



Sladen, Challenger Asteroidesk, 1889, p. 784 (Colombia, W. coast). 

 lAncUa omithopus Veriull, Trans. Conn. Acad., vol. 1, pt. 2, 1867, p. 330. 

 Mnckia diplax Perrier, Revision des Stell^rides, 1875, p.' 144 (California). 

 Linchia padfica, var. diplax Sladen, CTtaZkn^cr Asteroidea, 1889, p. 786 (California, listed with ??). 

 Phataria (Linckia) fascialis Monks, Proc. Acad. Nat. Sci. Phila., vol. 55, 1903, p. 351 (San Pedro, 



California). 

 Phataria (Linckia) unifascialis Gray, var. bifascialis, Monks, Proc. Acad. Nat. Sci. Phila., vol. 56, 



1904, p. 596. 



Diagnosis. — Rays one to nine, usually five; R extremely variable, no two rays 

 ordinarily the same length ; R = 90mm.; r = 8 mm.; R=ll r; width of ray at base = r. 

 Another average specimen: R = 60 mm.; r = 6 mm.; R=10 r. (Both measured by 

 longest ray.) Resembling closely L. guildingii Gray, from which the species differs 

 in having two instead of three regular lateral rows of plates ; in having not more than 

 five prominent abactinal plates on a transverse line across dorsum between the 

 superomarginals (instead of not less than seven in an adult of guildingii) ; in having 

 coarser abactinal granules; in having papular areas noticeably smaller than the 

 primary abactinal plates (larger in guildingii). 



Description. — The arrangement of plates on ray is as follows : between adambu- 

 lacrals and inferomarginals three longitudinal series of actinal intermediate plates 

 which are lengthened transversely to ray; then two regular series of marginal 

 plates, irregular or with four or five incipient lobes, the two series being joined by 

 small secondary ossicles; the dorsum between the two series of superomarginals is 

 paved with relatively few large plates with four or five incipient lobes, joined by 

 much smaller irregular oval or somewhat three-sided secondary plates. In a trans- 

 verse line across the ray between the two series of superomarginals there are from 

 three to five of the larger plates. Thus there are 3 + 3 actinal intermediates, 2 + 2 

 marginal regular series, +3 to 5 irregular abactinals — thirteen to fifteen plates 

 around the arm, omitting the adambulacrals and ambulacrals. 



Whole body is covered with rather coarse hemispherical granules, which on the 

 abactinal and lateral surface arc fairly uniform in size (being, however, slightly 



"Except in the decidedly aberrant Linckia marmorata (Michelin). 



