028 



RADIATA. 



nlisli tliis ohjt-rt hy inserting a sucker IhIwccii the valves. Occasionally, it is said, one of these 

 thirvi's has his liiij^t.r caught in the shell, in which case he snaps it off, prefening this sacrifice 

 ti) roinaiiiini; in caj)tivity. These creatures, like the brittle-stars, can reproduce tlieir limbs 

 which iuippeii to he broken off. In England these aniinals have the various names of Cross- 

 Fish, F'u't-Fiii'jers, DcvU's FuKjvrs, D. viTs IIuiuls, itc. 



Korbes describes several species of Asteridai on the Dritish coasts. Among them are the Spiny 

 Ckoss-Fism, Urastcr r//arialis, its ex})anded rays measuring twenty inches: the Common Cross- 

 I'lsii, If. ruhens, its rays measuring from nine to twelve inches: the Violet Cross-Fish, U- 

 violacea: the Kosv Cribella, Cribella rosea: the Eyed Cribella or Five-fingered Jack, C. 

 oculata : the Biitn's Foot Sea-Star, Palmipcs vicmbranaccus : the Knotty Cushion-Star, Goni- 

 aster equcstris : the Jiutthorn, Astcrias aurantiacn : •dudiliGLi^GTUoiis, Luidia/rar/iUissi?na. The 

 latter appears not only to have the power of casting away its arms entire, but of breaking them 

 voluntarily into little pieces. Forbes gives an amusing description of one which he caught in a 

 dredge. " Cautiously and anxiously," he says, *' I sank my bucket to a level with the dredge's 



mouth, and proceeded in the most gentle 

 mannerto introduce Luidia tothe purer ele- 

 ment. Whether the cold air was too much 

 for him, or the sight of the bucket too ter- 

 rific, I know not, but in a moment he pro- 

 ceeded to dissolve his corporation, and at 

 every mesh of the dredge his fragments 

 were seen escaping. In despair I grasped 

 at the largest, and brought up the extremity 

 of an arm with its terminating eye, the 

 spinous eyelid of which opened and closed 

 with something exceedingly like a smile of 

 derision." 



Some of the Sun-Stars are very beauti- 

 ful species; the Purple Sun-Star, Solaster 

 erideca, has eight rays, and the Common 

 Sun-Star, *S^. papposa, twelve or thirteen. 

 The colors in this are variable but bril- 

 liant — red, purple, green, and white. It 

 measures from nine to twelve inches across, 

 and feeds ravenously on shell-fish. These 

 are British species ; it is said we have similar ones on our northeastern coasts. 



THE COMMON EUROPEAN SUN-STAR. 



ORDER 4. CRINOIDEA. 



The Crinoidea, or Sea-Lilies — so called from the resemblance which many of them present to 

 flowers — were exceedingly abundant in former ages of the world ; and their remains often form 

 the great bulk of large masses of rock ; at the present day they are comparatively rare. They 

 are divided into several families. 



THE ENCRINID^. 



The family Encrinidce includes an immense number of fossil forms; and one or two are still to 

 be found in the West Indian seas. These animals were all supported upon a long stalk, at the 

 extremity of which they floated in the waters of the ancient seas, spreading their arms in every 

 direction in search of the small animals which constituted their food. Each of these arms, again, 

 was feathered with a double series of similarly-jointed appendages ; so that the number of cal- 

 careous pieces forming the skeleton of one of these animals was most enormous. It has been 

 calculated that one species, the Pentacrinus Briareus, must have been composed of at least one 

 hundred and fifty thousand joints ; and, " as each joint," according to Dr. Carpenter, " was fur- 



