Si 
7° 
IOI2 | 
THE 
PLAC 
REPRODUCTION 1ND 
ES OF THE FRESH-WATER 
(ANGUILLA VULGARIS). 
MONG the apodal fishes of the British Museum 
4 described by Kaup in 1856 was a 
parent, tape-like fish of about 8 cm. in 
SPAW NING- 
BEL 
trans- 
length, 
similar to the uppermost specimen in Fig. 1 here 
Larvz of the eel lus rostris) and tk 
slightly enlarged.—Johs. Schmid 
re produc ed. This received the name Leptoreskiuvu 
brevirostris, and came from the Stra’+3 of Messina, 
ally the only place in Europe from which 
Without knowing: it, 
«<ontribution the 
prac tic 
Leptocephali were known. 
the first 
Naup had given to 
uestion of the reproduction pf the eel. 
\bout forty years later ve learnt from Grassi 
NO. 2234, VOL, 89} 
NATURE 633 
and Calandruccio that Kaup’s Lept. brevirostris 
was no other than the larval form of the common 
eel living in the Mediterranean countries, a species 
supposed by some to be identical with the North 
European eel. These investigations were carried 
out at Messina, and left no doubt that the identi- 
fication was [he mysterious problem of 
eel was thus, about 18o=, 
for the first time opened up 
to scientific investigation. 
The Italian authors, 
however, did not stop 
the facts observed ; they 
put forward a number o 
suppositions regarding the 
reproduction of the eel, oc- 
currence of the eggs, mode 
of life of the larve, etc. 
Ege “No. 10” of Raffaele, 
found in the Mediter- 
ranean, Was supposed to 
belong to the common eel, 
the larvee were imagined to 
be demersal, deep-water 
fishes, and Grassi’s publi- 
cation in the Proceedings 
of the Royal Society of 
London in 1806 led every- 
one to believe, as the 
thing quite certain in the 
matter, that the spawning 
places of the eel are in the 
depths of the Mediterran- 
ean. Recent  investiga- 
tions have not altered the 
fact that L. brevirostris is 
the larval form of Anguilla 
vulgaris ; but the biological 
conclusions have not 
proved to be correct. 
In 1904 a new light was 
thrown upon the matter, 
when the Thor obtained 
specimen of Lept. 
rostris, 74 cm. in length, 
in the surface waters of 
the Atlantic of the 
Faeroes. In the same year 
a second specimen was 
taken west of Ireland by 
the Helga. The year 1904 
thus marked the beginning 
the second stage in the 
ution of the eel problem ; 
previously no Lept. brevi- 
vostris had been taken out- 
correct. 
the reproduction of the 
at 
of 
one 
bre V1i- 
west 
s elvers. All fi i . 
side the Mediterranean. 
\s Denmark is the country 
in which the eel fisheries are of the greatest 1 
portance, it seemed fitting that the Danish Com- 
mission carry the investigations further, 
ind for this purpose we had the advantage, not 
should 
only of a sea-going steamer, but also of the most 
modern apparatus—thanks to the experience and 
bility of the Director of the Danish Biological 
