DEVELOPMENT AND LIFE HISTORY OF SOME TELEOSTS 
547 
All the eggs of the European gobies that have been described or figured, so far 
as the present writers are familiar with the literature, are more or less elongate. Accord- 
ing to Petersen’s figures (1917) the eggs of Gobius niger are very elongate, the greater 
axis being about four times as long as the lesser one, and one end of the egg is larger 
than the other one. The adhesive foot is attached to the smaller end. The eggs of 
Gobius ruthensparri, as figured by Petersen (loc. cit.) and by Lebour (1919), are more 
or less pear-shaped, and the greater axis is less than 2 times as long as the lesser one. 
The adhesive foot is attached to the larger end of the egg. The eggs of Gobius microps 
according to Petersen’s figures (loc. cit.) are very similar to those of G. ruthensparri. 
However, the upper end of the egg is rather less pointed and the lower end has a slight 
pedicel to which the adhesive foot is attached. Lebour (1920) stated that the eggs 
of Gobius pictus are very similar to those of G. microps. The eggs of Gobius minulus, as 
figured by Petersen (loc. cit.) and also by Lebour (1920) are similar in shape to those 
of G. microps, being more elongate, however, as the greater axis is nearly two times as 
long as the lesser one. The adhesive foot is attached to a slight pedicel. The eggs 
of Gobius paganellus, as figured by Lebour (1919), are eliptical and very similar in 
shape to those of the American species, Gobiosoma bosci. The greater axis is rather 
more than two times as long as the lesser one, and the adhesive strands are attached 
to one pole of the longer axis. 
A rather remarkable similarity exists among the young of the American and 
European gobies, that have been studied, as shown principally by the works of Kuntz 
(1916), Petersen (1917), and Lebour (1919 and 1920), and by the present paper. The 
newly hatched larvae are of a small to a moderate size. Kuntz (loc. cit.) gave the 
length of the newly hatched larvae of the American species, Gobiosoma bosci and 
Gobionellus boleosoma, respectively as 2.0 and 1.2 mm; Lebour (1919) stated that the 
newly hatched larvae of the European species, Gobius paganellus and G. ruthensparri, are 
respectively 4.0 and 3.1 mm long and (1920) that those of G. microps and G. pictus 
are respectively 3.0 and 2.7 to 3.0 millimeters in length; and Petersen (loc. cit.) gave 
the length of the newly hatched young of two other European species, Gobius niger 
and G. minutus as 2.6 millimeters each. 
In general the body of the larvae is quite elongate and slender, varying somewhat 
among the species. The caudal portion is especially slender and tapers gradually 
to a point. The vent is placed somewhere near midbody length ; generally, however, 
rather nearer the tip of the tail (without the finfold) than the end of the snout. At 
hatcliing the head is rather rounded and the mouth tends to be horizontal and inferior. 
Very soon the mouth becomes rather oblique. However, as the adult stage is reached 
the mouth, in at least several species, tends to assume again more nearly the position 
occupied at hatching. When the caudal fin is first developed it either has a straight 
or a slightly rounded margin. As development of the fish progresses this fin tends to 
become more or less concave. Even in Gobionellus boleosoma, which has a moderately 
long and more or less pointed caudal fin in the adult, this fin is concave in the young 
that are around 8 mm long. In some species as in those of Gobiosoma, reported upon 
in this paper, the caudal fin does not become round, as in mature fish, until virtually 
all the adult characters are developed at a length of about 15 mm. The spinous 
dorsal usually develops somewhat later than the other fins in teleosts. In the gobies 
this fin develops especially late, or not until all the other fins are quite fully formed. 
The body in larval gobies generally is quite transparent and often the notochord 
or vertebrae are visible in part. The plainly visible air bladder, commonly with a 
crescent-shaped black area over it, is characteristic. Usually a few pigment spots 
are present at hatching and others soon appear. General pigmentation, however, 
