54 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxvn. 



IV. 



AMERICAN EPICARIDEA. 



American Epicaridea are represented in the following four families: 

 Bopvridie, Dajid;e, Cryptoniscidtv, and Entouiscida?. At the present 

 time no representatives- of the Entoniscid^e are known to the North 

 American fauna, and no representatives of the Dajidte have been 

 recorded from South American waters. 



In the following pages the forms added to the list given of those 

 already known are all representatives of the family Bopyrida?. The 

 material studied belongs to the U. S. National Museum and was 

 mostly collected by the U. S. Fish Commission steamer Albatross. 

 Other collectors are Mr. Henry Hemphill, Mr. George M. Gray, Mr. 

 W. C. Kendall, Dr. C. W. Richmond, Mr. J. B. Henderson, jr., Mr. 

 C. T. Simpson, and Dr. G. Brown Goode. These collections were made 

 at different times and in various localities. Some specimens were also 

 sent from Union University to the U. S. National Museum; they 

 were collected by Prof. H. E. Webster. 



Following the classitication of G. O. Sars,"* who combines the 

 three families of Giard and Bonnier, Cyproniscida?, Cal)iropsidie, and 

 Cryptoniscidie, into one family. Cryptoniscidge, the form Clypeoniscus 

 melneHl Giard and Bonnier has been assigned to the family Crypto- 

 niscida?. Sars also cancels the family Microniscida\ for he considers 

 31icro)iis<3u-'<, the only known genus, to represent not an adult condition, 

 but only a transitory larval stage in different Epicaridea, The Micro- 

 niscus stage Sars found to be intermediate between the two larval 

 stages previously known, the larva of the first stage and the Crypto- 

 niscus stage, and the Microniscus larvie of two different Epicarid 

 families was proved to be alwa3's parasitic on Copepoda. Giard and 

 Bonnier do not accept Sars's conclusions, but assign to Microniscus the 

 rank of a separate family. Microniscida\ which they believe represents 

 the ancestral form from which the other Epicaridea have descended. 



Contrary, also, to the hypothesis of Giard and Bonnier, who write 

 that one species of parasite can not be found on different species of 

 host, Sars'' has pointed out that for PJiry.mn ahdoitunalis Kroyer ten 

 different species of host have been recorded, representatives of two 

 different genera, S2jlr<>))toc<(r!s and Pandalus,' for Bopyroides hippo- 

 hjtes (Kroyer), three different species of Spirontocaris; for Bopyims 

 squillarum Latreille, three different species of Leander,' for Pseudione 

 ajfinls G. O. Sars, two different species of Pandalus; for Pseudione 

 hytidiiianni (Spence Bate and Westwood), two different species of 

 Kupxicjurus; for Pseudione crenulata G. O. Sars, two species of 



"Crustacea of Norway, II, 1899, pp. 193-195. 

 i'ldem, pp. 198, 199. 



