I 



122 FxiSCIOLES OF STAEFISHES. 



its abactinal pouch is remarkably uniform in groups apparently differing so 

 widely as the extreme pentagonal Starfishes, and the long slender-armed 

 genera like Ophidiaster, Asteracanthion, or even the apparently abnormal 

 group to which Brisinga, Pycnopodia, and Crossaster belong. 



I do not give a list of our North American Starfishes, much less a 

 Synonymic Catalogue, as it would be most incomplete and premature. 

 Quite a number of species collected by Mr. Pourtales in deep water be- 

 tween Florida and Cuba are at present in the hands of Professor Perrier 

 for determination ; of these several are undoubtedly new to our fauna. 

 Numerous additions have recently been made by Professor Verrill, while 

 engaged on the dredgings made in connection with the United States 

 Fish Commission. In addition the " Challenger " expedition, while cruising 

 in the Atlantic from Halifax to Bermudas, hence to New York, and then to 

 St. Thomas, added quite a number of remarkable forms to our American 

 species. As these collections are either in process of identification or 

 about to be worked up, any general list now given would soon become 

 antiquated. The Starfish fauna of North America, as far as now known, 

 can be made out with sufficient accuracy from the articles by Professor Per- 

 rier on the " Stellerides du Musseum in the Archives de Zoologie Experi- 

 mentale " for 1875 and 1876, although the Synonymy he has adopted 

 for several of our species will probably be modified Avhen larger material 

 than is now available has been collected. The principal localities of speci- 

 mens in the Museum collections are added. 



