MYXINOIDS. 
1195 
places it may lie dug up in numbers, after the stream 
has been dammed above the spot. Its Swedish name 
of lindl (Flax Eel) is derived from its habit of creep- 
ing among flax laid in the water to rot. In August 
the metamorphosis begins, and by the New Year or 
soon afterwards it is completed. The organs of genera- 
tion become distinct even earlier than this. 
After depositing its eggs the Lampern dies, ac- 
cording to Muller; and Trybom q has remarked, as 
evidence of this, that all the eggs in its ovaries are 
of the same size, so that no undeveloped ova, to be 
matured for another year’s spawning, can be detected. 
Petromyzon Planeri, according to their assumption, only 
lives a few months in its adult state. Of Petromyzon 
fluviatilis, on the other hand, Benecke assumes that 
the larvae migrate to the sea while undergoing 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 
Fam. M Y ] 
(Described by 
Outer branchial apertures either single or several (6‘ — 
Nasal duct open behint 
This remarkable family in its essential characters 
comes near to the preceding one, and lias therefore 
been coupled therewith to form the Cyclostomous order; 
but in other respects it exhibits such important dif- 
ferences from the Pctromyzonidce that at present, the 
links which 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 
a Forh. Alim. Sv. Fisk. Konf. Goteborg 1891, p. 88. 
6 According to Girard sometimes 14. 
Fatio has also observed, we must consequently regard 
it as an open question, whether most of the spent Lam- 
perns may not survive, but conceal themselves some- 
where beyond our ken, and possibly reappear at the 
spawning of the following year. 
The Lampern is a useful fish. For a good di- 
gestion it is excellent eating. Smoked and broiled it 
is a delicious whet before dinner; but for this purpose 
it is lit only during the cold season; in summer it is 
lean and dry. It is always a very valuable bait. It is 
taken in Jcassar (closely woven baskets, preferably of 
osier) and ndttingstockar (small square boxes made of 
thin boards perforated with small holes), which are 
placed between the stones where the current is of a 
suitable strength. The fishery succeeds best on dark 
nights, for the Lampern, like the Eel, is most active 
between sunset and dawn. 
The Lampern lias several Swedish names. Nejon- 
bga is originally a German word ( Neunauge ). In Hal- 
land it is known as stensugare (Stone-sucker). In Ble- 
kinge it is said to share with the preceding species the 
name of sillapipare. The smaller variety is called by 
Swartz igel-neinogon (Leech-Lamprey). 
I N 1 D JE. 
USTAF RETZIUS.) 
b ) on each side of the forepart of the body ( the throat). 
, penetrating the palate. 
an answer to these questions, so important to a con- 
ception of the origin from which the vertebrates have 
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 by ascertained facts. 
The Myxinoid family is represented in the modern 
fauna by ordy two genera, Bdellostoma and Myxine. The 
former, of which three species, inhabitants of the southern 
seas, have been distinguished, is characterized principally 
by the presence on each side of the body of six or more 
outer branchial apertures, each composing the opening 
duct of a gill-sac. In the genus Myxine, on the other 
hand, each side of the body is furnished with only one 
branchial aperture, the common orifice of the six gill-sacs. 
