ASTERIAS. 101 



serve this specimen as it was healthy. But in three days both rays 

 separated, lea\'ing the disc entirely free of appendages. AU went to 

 decay in a few days longer. 



A fifth ray may be added to four still subsisting to make up the 

 complement, or four may generate where only one remains. A single 

 ray, fig. 7, without incipient reproduction, appeared on July 30, as fig. 8, 

 when four had made considerable advance, as in the former specimen. 

 The fifth ray of a small specimen, defective, was ad^'aucing in the end of 

 December. Fig. 9. 



Many obscurities in the history of these two, the glacialis and 

 rube?is, whether the same or different, require elucidation. At present, I 

 incUne to conclude that the same facts apply alike to both. A specimen, 

 expanding twelve inches between the tips of the opposite rays, which 

 were of large size, being an inch and a half thick at the root, was entire- 

 ly of gallstone yellow. Having lain during the night in the open air 

 among sea-water, this external colour seemed to be altogether removed 

 when the specimen was washed in fresh water next morning. The sur- 

 face of the rays became nearly dull red lUac purple, which might have 

 led the observer to identif)' it at once as the Asterias glacialis. 



The pecuUar organization of the skin, the various pores by which it 

 is penetrated, and the subsidiary parts presented to view, and withdrawn 

 at will, merit farther investigation, for enabUng us to account for ex- 

 ternal appearances. 



From the aversion of the fishermen, both to the larger and smaller 

 genera of Star-fish, they were wont to rend them asunder. But on dis- 

 covering their purpose to be defeated by the reproductive energies of 

 their victims, they are now cast ashore, and left to perish. 



Plate XVI. 



Fig. 1. Asterias glacialis, the Northern Sea Star or Cross-fish, half size. 



2. Young specimen. 



3. Young specimen, originally white. 



4. Ray of fig 3 enlarged. 



