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to the Tachininæ and Dexiinæ , and tliese characters I have found 
confirmed by my subsequent studies on other larvæ of the named 
groups. In order to facilitate the comparison with the larva of 
Mydæa anomala I shall here recapitulate these characters. In 
the first stage the pharyngeal skeleton is undivided, it terminates 
in front in a single pointed tooth, on each side of which is found 
a little hook, which is not connected with the skeleton by an ar- 
ticulation. Only the anal stigmata are present. In the second 
stage the median tooth of the pharyngeal skeleton has disappeared, 
each lateral part of the pharyngeal skeleton has in front an ar- 
ticulation to which the mouth-hooks are articulated. Most species 
are amfipneustic, some few metapneustic and the anal spiracles 
have only two knobs. In the third stage the anterior part of the 
pharyngeal skeleton is connected with the posterior by an articula- 
tion. Most species are amfipneustic; the posterior spiracles are 
surrounded by a chitinous border and have at least three knobs. 
The larva of Mydæa anomala which species is, indeed, syste- 
matically rather distant from the Tachininæ and the Dexiinæ does 
not agree with the above characters. 
In the first stage there is no median tooth and the two lateral 
parts of the skeleton are separated from each other being only connected 
by means of a ventral bar; also the mouth hooks are articulated to 
the skeleton. In both the second and the third stages the skeleton 
has the same shape as in the 3. stage in the Tachininæ and 
Dexiinæ viz: the hooks being articulated with the anterior part 
of the skeleton and this part with the posterior. A distinctive 
mark between the two stages therefore cannot be found in the 
shape of the pharyngeal skeleton. The differences with respect to 
the shape of the mouth-hooks of Mydæa anomala are certainly 
due to the parasitism of the larva and therefore not suitable to 
afford general characters. 
Also with respect to the spiracles the larva of Mydæa ano¬ 
mala is different from those of the Tachininæ and Dexiinæ having 
three knobs in the anal stigmata of the second stage. 
