PALAEONTOLOGT OT THE LI AS. 73 



in detail all the organic remains such beds yield. The 

 Echinodermata enter largely into the composition of some 

 of them. Their spines are innumerable, but I have not 

 been able to obtain more than seven or eight perfect spe- 

 cimens of the sheU. This may be partly accounted for 

 when its complicated structure is considered. It is made 

 up of upwards of 2,000 plates ; and if the shell was 

 washed about before being covered up, the plates would 

 readily be disjointed and scattered. There are also frag- 

 mentary remains of the Star Fish. One of this family 

 has the power of breaking itself to pieces. Professor 

 Forbes mentions how he was taken in by one of them. 

 He had been dredging off the coast, and caught a Luidia, 

 which he got into bis boat perfect. When about to remove 

 it, to bis surprize, he found it had dissolved itself. The 

 next time he went out, he was determined not to be so 

 cheated ; he therefore carried a bücket, which, when a 

 Luidia came up, he sank to the mouth of the dredge, and 

 gently proceeded to raise the specimen. Whether the 

 cold air was too much for him, or the bücket too terrific, is 

 not known, but in a moment he proceeded to dissolve bis 

 Corporation, and at every mesh of the di-edge bis fragments 

 were seen escaping. In despair, he grasped at the largest, 

 and brought up the extremity of an arm, with its termina- 

 ting eye, the spinous eyelid of which opened and shut, 

 with something exceedingly like a mnk of derision. 



In the Maristone, Sponges are occasionally found; and two 

 new species of Corals have been described, from my collec- 

 tion, by M. Milne Edwards, the Director of the Garden of 

 Plauts, at Paris. Not more than two other species have, I 

 believe, been found in the Lias. 



From the investigations of scientific men, it is now known 

 that organic life exists in beings so iuconceivably small, as 

 1853, PART II. K 



