REVISION OF THE FISH FAMILY LIPARIDAE 6 



them by keys and descriptions. No one familiar with these fishes 

 should expect to identify them easily without correctly labeled spec- 

 imens at hand. 



The serial arrangement of the species differs from that presented 

 in any previous report. The large amount of material available has 

 made possible a careful study of the taxonomic value of all specific 

 characters. This has led to a clearer conception of the relationship 

 of the species. Many of the species, however, are based upon such 

 a combination of characters that it is difficult to trace out the different 

 lines of development. This accounts to a large extent for the different 

 views presented by writers concerning the relationship of various 

 species. 



Descriptions. — The specific descriptions are written in a uniform 

 manner in order to facihtate comparisons. 



In the measurements the length is given in millimeters and refers 

 to the distance between the tip of the snout and the tip of the caudal 

 fin. The other measurements are given in tenths of the length of 

 the body minus the caudal fin and of the length of the head. The 

 comparative measurements of certain parts proved to be of little or no 

 value. Of these some have been included and others omitted. Of 

 those omitted we refer to the length of the caudal fin, snout to dorsal, 

 snout to vent, pectoral to dorsal, interorbital width and disk to vent. 

 We have omitted some measurements in the species of one genus and 

 included them in the species of other genera because they proved to 

 be of greater value. See diagram illustrating the method of taking 

 measurements. The number given after "Locality" refers to Alba- 

 tross stations unless otherwise stated. 



These fishes are somewhat difficult to describe on account of the 

 texture of the body. Quite a few mistakes have been made in identifi- 

 cation and description. Many of the United States National 

 Museum specimens were found to be incorrectly labeled, and it was 

 not uncommon to find more than one species, and sometimes two 

 genera, in one bottle. This collection included eight undescribed 

 species and the very aberrant genus Nedoliparis. In the deep-sea 

 forms the dorsal and anal fins have to be dissected, sometimes under 

 water, in order to make accurate counts. The teeth should be 

 mounted on a slide and examined with the microscope. The micro- 

 scope and a powerful hand lens are necessary when working with 

 these fishes. Some of the important characters are lost with the 

 maceration of the skin. 



The distribution of the species as given is based solely upon the 

 material examined unless otherwise stated. As practically all the 

 material in America has been examined by the writer, records other 

 than those given here should be viewed with suspicion as possibly the 

 result of misidentification. 



