612 BULLETIN 82, UNITED STATES NATIONAL MUSEUM. 



He says also that it swims with medusa-like contractions. Bather immediately 

 replied, calling attention to its gregarious habits and its power of flotation or 

 movement from place to place. 



Perrier says that at Roscoff Antedon bifida is easily procured at the spring 

 tides. It inhabits the entire region opposite Isle Verte, between that island and 

 Isle de Bas, as far to the east as to the west. To the eastward Professor de Lacaze- 

 Duthiers showed them to Perrier in 1870 literally covering the stalks of the sea- 

 weeds. In that year Perrier found them also to the west, but less abundant, almost 

 opposite but a little to the left of the black beacon of Per-Roch. In two tides 

 Perrier secured there almost 300, without counting a quantity of young in all 

 stages of development, including pentacrinoids. Antedon bifida is very abundant 

 only below the Himanthalia lorea zone, attached to seaweeds or to the brown 

 and curled fuci which abound at the lower edge of the seaweed zone. 



Perrier records that sometimes individuals of Antedon bifida, almost always 

 of large size and of a very bright carmine, are found under stones which have 

 been turned over in a search for other animals. 



FOOD. 



| 



Duchassaing records that the stomach contents of a specimen of Isocrinus 

 decorus which he fished up in relatively very shallow water at Guadeloupe, French 

 West Indies, consisted only of the remains of small crustaceans. 



Bronn, summarizing previous accounts, wrote that the stomach contents of 

 Isocrinus were made up of the remains of small crustaceans, while those of the 

 comatulids consisted of diatoms such as Navicula, Bacillaria, Actinocyclus, and 

 Coscinodiscus, of Tethya, and of many types of entomostraca. 



W. B. Carpenter said in 1866 that in the very numerous specimens of Antedon 

 bifida from Arran, of which he examined the contents of the digestive cavity, he 

 never found anything other than microscopic organisms, and the abundance of the 

 horny rays of Peridinium tripos made it evident that in this locality that organism 

 is one of the principal articles of food. But in specimens from other localities 

 he found a more miscellaneous assemblage of alimentary particles, the most com- 

 monly recognizable forms being the horny casings of entomostraca or of the larvae 

 of higher crustaceans. 



In his account of Hyponome sarsii (the visceral mass of Zygometra micro- 

 discus) Loven states that in the ambulacral grooves he found masses consisting of 

 minute crustaceans, larval bivalves, and other remains of food. 



In 1876 W. B. Carpenter wrote that the contents of the alimentary canal of 

 Antedon bifida both in the pentacrinoid stage and in the adult consists of minute 

 entomostraca, diatoms, spores of algae, etc., but especially in his Lamlash speci- 

 mens of Peridinium tripos, which was usually very abundant in that locality. 



He also notes that the contents of the alimentary canals of the various types 

 of existing pentacrinites examined by him are of the same nature. 



P. H. Carpenter says that the food of a crinoid is considerably varied in its 

 nature, according to the character of the sea bottom on which it lives. The horny 

 casings of entomostraca and the larvae of larger Crustacea are frequently to 



