94 ECHINODERMA. 
lre Tribu, Duj. § Hup. Echin. (1862) p. 829. 
Typical Startishes, Gray, Syn. B. M. 42nd ed. (1840) p. 61. 
Asteriidee (s. em.), Sladen, Chall. Rep, Ast. (1889) p. xxxix. 
The Asteriide are cryptozonate Asteroids, with the reticular 
abactinal skeleton made up of small unequal plates carrying one or 
more small spines. The podia appear to be arranged in four rows. 
Major and minor pedicellariz, as a rule, both present. 
One genus: Asterias. 
Family 7. BRISINGIDA. 
Brisingidee, Sars, Remarkable Forms, ii. (1875) p. 101; Perrier, Nouv. 
Arch, Mus. vi. (1884) p. 188; Sladen, Chall. Rep. Ast. (1889) p. xl. 
Cryptozonate Euasteroidea, in which the reduction of the marginal 
plates is altogether or almost complete ; and the dorsal skeletal plates, 
if present, found only on the disk and the proximal portion of the 
arms; no intermediate ventral plates or any interbrachial septa. 
Two genera: Brisinga and Odinia. 
Class X. OPHIUROIDEA. 
Ophiura, Lamk. Syst. (1801) p. 350. 
Asterophidea, de Bl. Dict. Sci. Nat. 1x. (1850) p. 228: id. Actinol. 
(1834) p. 242. 
Ophiures, Agass. Mém. Soc. Neuch. 1. (1836) p. 192; id. Ann. Sei. 
Nat. vii. (1837) p. 287. 
Ophiurida, Gray, Syn. B. M. 42nd ed. (1840) p. 63; ad. Brit. Rad. 
(1848) p. 28. 
Ophiuride, Forbes, Brit. Starf. (1840) pp. xiv, 19; M. Tr. Syst. Ast. 
(1842) pp. 79, 81; Bronn, Klass. u. Ordn. (1860) p. 283. 
Ophiure, Forbes, Mem. Wern. Soc. viii. (1839) p. 124; Diib. § Kor. 
et. Akad. Hdlg. 1844 (1846) p. 233. 
Ophiurides, Duy. § Hup. Ech. (1862) p. 219. 
Ophiuroidea, Norman, Ann. § Mag. xv. (1865) p. 104; Ljungman, 
Gifu. Vet. Akad, Forhlg. 1866 (1867), p. 803; Cuénot, Arch. Zool. 
expér, Vi. (1888) p. 33; Bell, Ann. § Mag. viii. (1891) p. 215. 
The Ophiuroidea are caliculate, actinogonidial, eleutherozoic, liss- 
actinic Echinoderms in which there is no distinct ambulacral groove. 
The “arms ” are sharply marked off from the disk, are very rarely 
more than five in number, and are sometimes elaborately branched. 
The digestive system, which is aproctous, and the generative are 
confined to the area of the disk, as is also the specialized respiratory 
apparatus which, typically, takes the form of deep clefts. 
