ECHINODERMA. 
113 
pinnules at their sides, and the sucking-feet have the form of 
tentacles. 
The stalked representatives of this Order are placed on tables and 
brackets near the south door, and are worthy of being particularly 
noticed for their fine preservation, size, and beauty. The largest 
specimen of Pentacrtnus decorus was taken on a telegraph-wire, 
to the covering of which the stalk of the Crinoid is still attached. 
Metacrinus is a more lately discovered genus, which appears to be 
confined to the eastern seas. 
A few dried unstalked Crinoids are shown in Table-case 1 ; 
these show the leading modifications of structure in the two great 
genera Antedon and Actinometra. 
Asteeoidea. — This Order comprises Echinoderms with a de- 
pressed body of pentagonal or star-like shape, to the ventral surface 
of which the ambulacral feet are confined. The rays are more or 
Fig. 7. 
Comet form of Linckia. 
less elongate movable arms, with skeletal structures, which consist 
of transversely arranged, paired, calcareous plates, articulated with 
