MYXIXOID,S. 



111(5 



|ilaces it lUMy be dug vi}) in niinihers, after the stream 

 has Ix'cii (laniiued above tlic s|Kit. Its Swedish name 

 of lindl (Flax Eel) is derived frum its iiabit of creep- 

 ing among flax laid in the watcn- to rot. In August 

 the raetaniorpliosis begins, and by tlic New "^'ear or 

 soon afterwards it is completed. The organs of genera- 

 tion become distinct even earlier than this. 



After depositing its eggs the Lampcn-n dies, ac- 

 cording to MrLLEii; and 'riiYiioji" has remarked, as 

 evidence of tins, that all the eggs in its ovaries are 

 of tile same size, so that no undeveloped ova, to be 

 matured for another year's s})awning, can be detected. 

 Fetrnm/i^oii I'hnieri, according to their assumption, only 

 lives a few montiis in its adult state. Of Fetromyzon 

 Jiuviattlis, ou the other hand, Ijenfxke assumes that 

 the larvffi migrate to the sea while tuidergoing meta- 

 morphosis; and their life in salt water is unknown. 

 But the fact is that sexually mature individuals of both 

 varieties are found differing so widely in size that it 

 is almost inconceivable that they can be of the same 

 age. It would thus appear that some attain maturity 

 the very first year after the metamorphosis, others not 

 until several years have elapsed. For the present, as 



Fatio has also observed, we must consequently regard 

 it as an open (piestion, whether most of the spent Lam- 

 perns may not survive, but conceal themselves some- 

 where beyond our ken, and jjossibly reaj)pear at the 

 spawning of tlu; following year. 



The Lampern is a useful tish. For a gijod di- 

 gestion it is excellent eating. Smoked and broiled it 

 is a delicious wiiet before dinner; lint f<ir tiiis purpose 

 it is tit only during the cold season; in siuumer it is 

 lean and dry. It is always a very valuable bait. It is 

 taken in /crt.s'.sar (closely woven baskets, ]jreferably of 

 osier) and ndttingstnchar (small square boxes made of 

 thin boards perforated witli small iioles), wliich are 

 placed betw(!en the stones where the current is of a 

 suitable strengtii. The fishery succeeds best on dark 

 nights, for the Lampern, like the Eel, is most active 

 between sunset and dawn. 



The Lamjiern has several Swedish names. Nejon- 

 oijd is originally a German word {Neunauge). In Hal- 

 land it is known as sfensiigare (Stone-sucker). In Ble- 

 kinge it is said to share witli the preceding species the 

 name of ■■iillajtijxire. The smaller variety is called by 

 SwAirrz i(ji'l-noA)id(/0)i (Leech-Lamprey). 



Outer branchial apertures 



fam. myxinidj:. 



(Described by (ir.STAF Ketzius.) 



iither single or sereral {U — 7'') on each side of the forepart of the Ijody {the throat). 

 Nasal duct open behind, penetrating the palate. 



This remarkable family in its essential characters 

 comes near to the preceding one, and has therefore 

 been cou]iled therewith to form the Cyclostomous order; 

 but in other respects it exhibits such important dif- 

 ferences from the Petromiizonidce that at present, the 

 links whicii would seem to have once connected them 

 having apparently disappeared, the investigation of their 

 mutual relationship and collocation in the phylogenetic 

 system is no easy task. 



Perhaps they are both more or less retrogressive 

 forms; this is probable at least with respect to the 

 Myxinoids. In several respects, however, the latter 

 display obviously lower characters than the family of 

 the Lampreys. 



The time may possibly come where the ontogenetic 

 evolution of the Myxinoids may in some degree supply 



•" Forh. AUm. Sv. Fisk. Konf. Goteborg 1891. p. 88. 

 ' .According to Girard soinetiiiies 14. 



an answer to these questions, so im])ortant to a con- 

 cejation of tlie origin from which tlie vertebrates liave 

 sprung; but as long as the said evolution of the Myxi- 

 noids, in spite of the pains devoted to its study, re- 

 mains all but unknown, the proper course is to refrain 

 from drawing any conclusions that are not borne out 

 to the full liy ascertained facts. 



The Myxinoid family is represented in the modern 

 fauna h\ only t^vo genera, Bdellostoma and Myxine. The 

 former, of which three species, inhabitants of the southern 

 seas, have l)een distinguished, is characterized principally 

 by the ])resence on each side of the body of six or more 

 outer branchial ajjertures, each composing the opening 

 duct of a gill-sac. In the geiuis My.vine, on the other 

 hand, each side of the body is furnished with only one 

 branchial aperture, the common orifice of the six gill-sacs. 



