4 U.S. NATIONAL MUSETJM BULLETIN 271 



has not been exploited fully in making advances in ecological, physio- 

 logical, and genetical studies, although most of those special studies 

 so far undertaken have been pursued in the northeastern Atlantic. 



Intensive work has been accomphshed in antarctic seas but the 

 fauna there needs to be placed on a Sarsian basis with full illustra- 

 tions and descriptions. The works of Chevreux (1906c, 1912b) are 

 notable for that region, but numerous sticky problems resulting from 

 other studies have not been clarified there. 



The remaining faunas are sketchily known. An imbalanced em- 

 phasis on the deep-sea is occurring in this decade, but this has helped 

 bring into focus many problems in the higher taxa of amphipods. 

 Since World War II research on the marine species has been meager, 

 because more than 90 percent of the printed pages have been pro- 

 duced by fewer than 10 taxonomists (Zoological Record, years 

 1953-60). 



Morphological Terminology 



The taxonomic assessment of gammaridean morphology is almost 

 always stated in subjective terms: in words and phrases which, 

 through experience, taxonomists have come to understand and 

 visualize easily, but which are difficult to convey with mensurative 

 precision. There is no current solution to this difficulty but taxono- 

 mists may eventually be able to compile an illustrated handbook 

 in which all possible shapes and relative proportions can be figured, 

 named, and coded. Identifications may then be amenable to mechan- 

 ical analysis. Meanwhile one must work with terms such as "strong, 

 large, small, feeble, weak, minute, elongate, shortened" and various 

 adjectives with the modifier "sub," such as "subquadrate" and 

 "subacute". I have used these terms everywhere in this handbook, 

 but have attempted to provide illustrations as a demonstration of 

 their extent, for the degree varies in the different famiUes. For in- 

 stance, gnathopods of the genus Apherusa are "feeble" in com- 

 parison to those of its famiUal congener Calliopius, but they are 

 scarcely as feeble as the gnathopods of the Acanthonotozomatidae. 

 The term "subacute" apparently has come to mean a shape that 

 has the overall appearance of sharpness but which terminally is 

 softly rounded. The term "subcorneal" apparently refers to a 2- 

 dimensional, rather than a geometric cone but the adjective is not 

 necessarily synonymous with "subacute," for a subcorneal process 

 may have a subacute apex. The term "quadrate" has often been 

 appHed to a squared-off shape of an otherwise imperfect rectangle 

 or in simpler fashion as reference to one pair of sides occurring at 

 right angles to each other. "Subquadrate" should refer to sides not 



