GAMJVIARIDEAN AMPHIPODA 35 



large teeth on pleonites 4 and 5 and a slightly enlarged tooth of the 

 third pleonal epimeron. 



Material. — Station 7358 (2). 



Distribution. — Southern California to middle Baja California, 

 366-1821 m. 



Lysianassidae 



Nomenclature. — Unfortunately the nomenclature of several old di- 

 verse lysianassid genera is erroneous. The morphology and classifica- 

 tion of various species in some of those genera are discussed in sequel 

 as if there were no nomenclatural problems to add further to tlie con- 

 fusion. The nomenclature cannot be stabilized in this writing without 

 rendering the discussion of morphological characters unintelligible 

 and, therefore, the necessary changes in names are ignored. Invalid 

 names are marked with quotation marks throughout the text. A paper 

 has been submitted to press by the writer clarifying some of the 

 nomenclature and the folio whig remarks anticipate that thesis. 



Taxa Related to Hippomedon, Schisturella, "Tryphosa," and Uristes 



Several deep-sea lysianassicls described in the last few decades have 

 confounded the generic classification established by Sars (1895) and 

 Stebbing ( 1906) . The basic structure of that classification is neverthe- 

 less pristine. 



The systematics of marine Gammaridea have ahvays been based 

 mainly on the fauna of Europe because few comprehensive revisions in- 

 cluding extrinsic faunas have been made since 1906. But since that 

 time numerous species and genera have been described outside of 

 Europe. Some of the genera have been based on what were considered, 

 at the time of their description, to be good qualitative cliaracters but 

 which have been linked, more and more, to some of the European genera 

 through species with intergrading characters. On the other hand, 

 some of the extrinsic species assigned to European genera because of 

 general resemblance are now known to be strongly distinct in their 

 generic cliaracters. An example of the first case is the '■^Lysianassa- 

 problem," in which extrinsic members of Lysianassa have been made 

 the type-species of genera such as Lysianoj^sis (New England) , Amga 

 (CaMiornia) , /Shoemakerella (Caribbean Sea), Arugella (Indonesia), 

 and Pronannonyx (SW Africa). 



Lysianassidae of north boreal regions have been revised recently 

 by Gurjanova (1962). She has established some criteria and set some 

 precedents having critical value in reclassifying all Lysianassidae. 



