20 THE AMERICAN NATURALIST. [Vor. XXXVI. 
*lingua" and a pair of organs termed “ paraglossz " by writers 
on the Thysanura and Collembola. As the term “ paraglossae " 
has long been used for a part of the labium or second maxilla, 
Folsom I deed maintains that it should not be applied to a 
part of the hypopharynx, and 
proposes for these paired organs 
the term superlingue. 
In his work on the develop- 
ment of apterygote insects, Uzel 
(98) showed that the lingua arises 
between the rudiments of the 
maxilla; hence it may be regarded 
it LIT ___} as pertaining to the sternum of 
Pio. 8.— Head of embryo of Anurida, — the maxillary segment. Uzel also 
showed that the superlinguz arise 
as a pair of appendages between the mandibles and the maxil- 
lae. , This indicates the existence of a segment between the 
mandibular and the maxillary segments. 
Similar results were obtained by Folsom ('00) in his work 
on the development of the mouth parts of Anurida. Fig. 8 
is copied from Folsom and illustrates the relative positions of 
the rudiments of the mouth parts. To Folsom also belongs 
the credit of completing the : 
evidence of the existence of a 
superlingual segment, by demon- 
strating the existence of a pair 
of primary ganglia between those 
of the mandibular and of the 
maxillary segments (Fig. 9, 5). 
And in a preliminary paper (99b), 
he set forth the first complete 
account of what promises to be 
our final view regarding the seg- — 
mentation of the head. ——— 
In confismation of the view 
bees the: sut 'sophageal ganglion consists of four pairs of 
| y ganglia, it should be mentioned that wis ago Patten 
a ‘these ganglia. It has been believed , however, that 













