IS94.1 
319 
[Packard. 
like a blunt hair, and only as long as the second joint is thick. 
The mouth-parts are composed of a well-developed pair of 
mandibles, wliile the maxillae, especially those of the second pair, 
are quite rudimentary. 
The mandibles (Fig. 3, o, 
md) seen from the side are 
broad, triangular, ending in 
two teeth, but in a jjartly pro- 
file view are seen to end in 
five rounded teeth. Compared 
with those of other larvae, 
they are more like those of 
coleopterous larvae than dip- 
terous, being less modified and 
degenerate than in the latter. 
The maxillae (Figs. 3-6, 
'mo;) are somewhat reduced, 
not divided into an inner ajid 
outer lobe as in the eucepha- 
lous dipterous larvae, being 
represented by a two- join ted 
long as the antennae. The distal 
long as the basal one, and is 
7>t.c mx 
Fig. 4. Head of freshly hatched 
larva of Pulex canis ; e.b, egg- 
breaker; ant, antennae ; jJuZ, man- 
dible; mx, maxilla; mx' , 2d max- 
illa (labium). — Author del. 
appendage, about half as 
joint is a little over twice as 
mx. 
Fig. 5. Mouth-parts of freshly iiatched larva of Pulex canis; mx, 
maxilla; c, maxillary capsule; r, styles or rods for attachment of the 
retractor muscles; md, mandibles from different sides; mx', teeth arising 
from the labium or second maxillae. — Author del. 
thick, rounded at the end, and bears just within the extremity 
on tlie inner edge two rows of stout, blunt spinules, the inner of 
the two rows being composed of four spinules. Each maxilla is 
