Systematics of certain Chilognathous Diplopods. 527 
palpiform, four-jointed, the sterno-coxal 
plate enormous, wide, deeply excavated 
behind for the reception of the penis; 
sterna of fourth, fifth, and sixth seg- 
ments fused to the terga; appendages 
and sterna of sixth segment normal. 
Female with sternum and appendages 
of second segment greatly reduced ; 
genital orifices protected by large chiti- 
nous plates, sternum of third segment 
united to the tergum............... . Paraiulide. 
b?, Male with legs of first pair five-jointed, 
of second pair small but not palpiform, 
armed with a long claw, consisting of 
five segments, in contact at the base and 
rising from the distal extremity of a 
long cylindrical column, representing 
the sterno-coxal elements, and not exca- 
vated behind for the lodgment of the 
penis; sterna of fourth, fifth, and sixth 
segments not fused to terga; anterior 
appendages of sixth segment normally 
pediform, the posterior reduced to a 
conical three-jointed bud concealed 
by the tergum and attached to the en- 
larged sternal plate, which is produced 
inferiorly into a pair of long blade-like 
excrescences. Female with sternum 
and appendages of second segment 
normal, as in Julus; no special sclerites 
developed in connexion with the genital 
apertures, sternum of third segment free 
EOE KETO UNG, air. odes cuayeseas (ove es ese & Mongoliulide. 
bt, Male with first leg short, greatly modified 
to form a broad, thickly chitinized, at most 
two-jointed sclerite, the basal segment 
very short, the distal much longer and, at 
least sometimes, hooked apically ; second 
legs normal in length, longer than the first, 
their coxee separated by a very distinct 
median suture; gnathochilarium unmodi- 
fied; promentum triangular, lingual lobes 
converging distally on each side of it; 
coleopods consisting of a single sclerite 
composed of two pieces united by a suture 
but not independently movable, the ante- 
rior (inner) piece much shorter than the 
posterior (outer). Female with second 
leg normal in size and structure, its cox 
thickened and strongly chitinized, no dis- 
tinct genital plates like those of Paraiwlus. Peromopide *, 
* Apart from its mandibles Peromopus, of waich I have seen one male 
and one female belonging to different species, is much more nearly related 
to the Lulide than to the Paraiulide and Mongoliulide, 
