Verrill, Notes on Radiata. 339 



The Araucaxiax Province — This appcjirs to extend from near 

 Valdiva to the south-western coast of Patagonia, but its southern 

 portion is very little known. Dana places its southern boundary at 

 lat. 50°, which would make its length about 900 miles. 



The FiEGiAX Province. — This includes southern Patagonia and 

 the adjacent Islands. Several peculiar and interesting Echinodcrms 

 have been described from this Fauna, some of which, as Asterias 

 antarctica and " Cuvieria imtKrctk-a,''^ recall the forms of the Arctic 

 regions, while there are other genera, as IVlpyliis, that are quite 

 peculiar. 



Co7npar/son of the Tropical JEchinoderm Faunce of the East and 

 West Coasts of America. 



The question of identity between certain species found upon the 

 Atlantic and Pacific coasts of Centi-al Amei'ica is of great interest 

 both to the Zoologist and Geologist, and has received much attention 

 from various writers. That the two Faun:i3 are remarkably similar 

 in many respects, and have large numbers of closely allied, repre- 

 sentative or analogous species, is admitted by all who have written 

 upon the subject. Sevei'al authors also admit a certain number of 

 species which are identical or undistinguishable. Thus of Mollusca, 

 Dr. P. P. Carj^enter* admits 35 species as identical between the two 

 coasts; 34 additional ones that may prove to be identical ; 41 that 

 are " really separated, but by slight differences ;" 26 that are " analo- 

 gous but quite distinct species." In addition to these he admits 15 

 species as probably common to the west coast of America and the 

 west and south coasts of Africa. Prof C. B. Adamsf did not admit 

 any species as common to Panama and the West Indies, except 

 (Jrepldula ungidformls. 



Prof Dana, Dr. Stimpson,J and others admit several species ot 

 Crustacea as common to the two coasts. In the collections of Mr. 



* Report of the British Association for the advancement of Science, 1856. 

 f Annals of the Lyceum of Natural History of New York, v, 1852. 

 \ Notes on North American Crustacea. Annals Lyceum Nai. Hist, of N. Y., 1858 

 and 1850. In these papers the following species are indicated from both coasts : 

 Petrolisthes armatus Stimp. Gronius ruber Stimp. 



Ozitis perlatus Stimp. N'autilograpsus minutiis M. Edw. 



Eriphia gonagra M. Edw. Acanthopus planissimus Dana. 



Cillinectes diacanthus Stimp. Domecia hispida Souly. 



Mr. Albert Ordway has satisfactorily separated the western species of Callinectes 

 from those of the West Indies, (Boston .lournal Nat. History, vol. vii, 1863). Concern- 

 ing some of the other species Dr. Stimpson, himself, expresses doubt, owing to the 

 want of sufficient specimens for ascertainiug the constancy of slight differences. 



