Genera of Paralepididae — HARRY 
227 
genera Magnisudis, Paralepis, and Notolepis by 
the complete absence of scales, by the greater 
length of the mandibular teeth, by the ar- 
rangement of the teeth on each gillraker into 
a single row of short needle-like structures, 
and by the reduction of the pharyngobran- 
chial teeth to a single patch. 
The ancestral stock evidently split rather 
early into three developmental lines. One of 
these, which can be designated as the sub- 
genus Lestidiops, is the most conservative. It 
is characterized by a somewhat massive head 
and blunt snout, a deep and heavy mandi- 
bular symphysis, the absence of nonossified 
prolongations on the jaws, a low number of 
anal rays (26-28), and the position of the 
dorsal fin in the middle third of the space 
between pelvic and anal fins. 
The second evolutionary line, the subgenus 
Lestidium, comprises the majority of the spe- 
cies from both the Atlantic and the South 
Pacific. It has retained a relatively low number 
of anal rays (27-33) but has developed a 
slightly less massive head and snout and, in 
the most specialized species, a prominent, 
nonossified prolongation on the lower jaw 
{neks, pacificum, ntidum). In all members of 
the subgenus Lestidium the position of the 
dorsal fin is over the pelvic fins. The third 
evolutionary line of the genus Lestidium, 
which is similar to the subgenus Lestidiops in 
the position of the dorsal fin in the middle 
third of the distance between the pelvic and 
anal fins, constitutes a new subgenus, Lestro- 
lepis. This clearly delimited group of the genus 
Lestidium is distinguished by a high number 
of anal rays (33-49), a slender and elongate 
lower jaw, a distinctive preorbital pigmenta- 
tion, a well-developed, nonossified prolonga- 
tion of the lower jaw, and the position of the 
dorsal fin. 
The remaining Paralepididae have been 
placed by Ege in the genus Macroparalepis. 
He differentiated this group on the basis of 
four characters, presumed to be unique: (1) 
the nonossified prolongation on the tip of the 
lower jaw; (2) the shape of the lateral-line 
segments, which have the greatest height at 
or very near the anterior margin; (3) the pres- 
ence of two pores above and below on each 
FIG. 6. Postlarva of Lestidium sphyraenoides (Risso), 
approximately 8 mm. in length, showing the position 
of the intestine behind the eye (after Ege, 1930). 
lateral-line segment; and (4) the position of 
the intestine under the eye in postlarvae (see 
Figs. 6 and 7). My investigations show that 
at least three of these characters are shared by 
other paralepidids, and it may be questionable 
that the other is unique to Macroparalepis. 
The subgenera Lestidium and Lestrolepis both 
have nonossified prolongations of the lower 
jaw, and many species of the genus Lestidium 
possess characters 2 and 3. The condition 
stated for (3) has been found to be the basic 
pore pattern for all naked genera and is not 
unique to any particular paralepidid group. 
In regard to point 4, Ege has stated in corre- 
spondence that his groups I and II of ^'Para- 
lepsis" both have the same postlarval develop- 
ment, with the intestine behind the head, dif- 
fering markedly from that of Macroparalepis. 
No one, however, has been able to examine 
the postlarvae of the species in Lestidium that 
most closely approach Macroparalepis, and 
there may be some intergradation in these 
larval characters. 
Fig. 7. Postlarva of Macroparalepis brevis Ege, ap- 
proximately 8 mm. in length, showing the position of 
the intestine below the eye. (This illustration prepared 
from a tracing generously supplied by Ege.) 
Ege considers that Macroparalepis is very 
distinct and that Lestidium [Paralepis group II] 
is much more closely related to Paralepis [Pa- 
ralepis group I] than it is to Macroparalepis. 
This opinion is based primarily on the dif- 
ferences in postlarval development. My con- 
clusions are entirely the opposite in regard to 
Ege’s Macroparalepis group I. In every adult 
