294 ELEMENTS OF COMPARATIVE ZOOLOGY. 



rounding the month. There are a few forms in which the 

 arms branch again and again, and since when captured these 

 forms bend the arms inwards towards the mouth, giving 



FIG. 133. Crinoid (Pentacrlnus) half FIG. 184. Mouth area of a crinoid 

 natural size. From Brehm. ( Comatula) showing the course of 



the intestine leading from the 

 mouth (m > to the vent (a). 0, grooves 

 leading from anus to mouth. 



a somewhat basket-like appearance, these are known as 

 "basket-fish/' The name brittle-stars is due to the fact 

 that in some the arms are very easily broken. A few 

 brittle-stars produce living young. 



