LYCODIN^,. 



7 



The pectoral fins often give good specific characters. The number of rays in the present 

 species varies from 15 to 23, but the variation within the individual species is sometimes very limited. 

 The length of the pectoral fin also is sometimes a good determining character between nearly allied 

 species. The posterior margin of the pectoral fin is in general rounded, but the condition in L. 

 eiidipleuyostictus (Tab. Ill, fig. i) is characteristic in tliat the lower rays are somewhat longer than the 

 middle ones, so that an indentation occurs (the same nia\^ also occur in individuals of L. frigidus, 

 see Tab. V, fig. i a). 



Other characters which might be taken into consideration, though not to so great an extent, 

 are the relative height of the body (the dimension chosen in this work for the greater or less 

 elongation is always the height over the anus, which is to some e.xtent independent of distension caused 

 by food or sexual products), the relative length of the head (which is nevertheless ratlier variable 

 within the individual species, the males as a rule having longer heads than tlie females or young), 

 size of the eyes, condition of the teeth etc. 



A gap in the present work is the almost entire absence of the structural anatomy; I 

 must leave this aspect of the diagnosis of the Lycodinse to others who can afford the necessary time. 

 I have only been able to examine the appendices pyloncce, which in the present species of the genus 

 Lycodes are always two and very small, with exception of L. esmarkii Coll., where the}- are wanting 

 altogether. 



Geograi^hical Distribution. A not unimportant factor to be taken into account in deter- 

 mining a specimen, is where it was found, each species hawing its characteristic, horizontal and vertical 

 distribution, as will be mentioned in detail in the special part. A summary is given on p. 9—10 for 

 orientating the species which inhabit the various seas within the entire area; but though this 

 summary is based on a large amount of material, the possibility is of course not excluded that future 

 investigations mav still find .new > forms within these seas. 



Lycenchelys Gill and Lycodonus Goode & Bean. 



To the genus Lycenchelys I have referred 4 European and Greenland species: L.murcena Coll., 

 L. sarsii Coll., L. kolthoffi Jensen and L. ingoljianus Jensen, the determination of which does not 

 cause great difficulty. A good specific character is formed seemingly by the large pits of the lateral 

 line along the upper jaw and under the eye. In L. ingolfiantcs their number is 8, in the others onl\- 

 7. Other good characters are to be found in the distance of the dorsal fin from the snout, the relative 

 length of the head and the number of rays in the pectoral fins. The colouration in L. vtuycBna is 

 uniform, and this species also is restricted to great depths (340—620 f.); what the condition is in L. 

 ingolfianus is not known, as only one adult specimen (uniformly coloured) has been found; L. kolthoffi 

 has a strongly spotted (marbled) colouration; L. sarsii has dark markings in the young becoming 

 indistinct in the older stages. Each of these four species has its own separate area of the sea, so 

 that one can conclude from the region alone which species is to hand. — Cf. for the rest, the synoptical 

 table which is given later. 



