situation of the immovable eye-stalks beneath and parallel with the anterior border of the 

 carapace, is represented by 4 species. Wi/l. hptodactyla (Will.-Suhm), the first discovered 

 species, does not only occur in the Atlantic, north and south of the Equator, but has also been 

 observed off the west coast of South America. The Gulf of Panama is inhabited by Will, 

 inornata Fax., which may easily be recognized by the few spines on the margin and dorsal 

 ridges of the carapace, while Will, forceps A. M.-Edw., the carapace of which is more inflated, 

 has been obtained by the "Blake" Expedition in the Gulf of Me.xico. The fourth species, 

 finally, is Will, indica Alcock from the Bay of Bengal. 



The recent Eryonidae are represented by about 45 species and 3 varieties, that are 

 enumerated in the following List, which indicates also the localities where the species have been 

 observed and the depths at which they have been obtained. The greatest depth at which a 

 species of this family was taken, was 2225 fathoms off the coast of South America, where- 

 from Will, leptodactyla has been recorded. 



LIST OF ALL THE SPECIES OF RECENT ERYONIDAE, KNOWN 

 AT PRESENT, November 1915 '). 



I. Genus Stereomastis Sp. Bate 1888. 



1) The species collected by the "Siboga" are marked with an asterisk and the new species are printed in a more heavy type. 



2) The female, collected by the Challenger Expedition at this Station, belongs probably to another species. 



