spiratory organs, as in
Urotricha.

Family -- Phrynichidae (_Phrynichus_, _Damon_).
" Admetidae (_Admetus_, _Heterophrynus_).
" Charontidae (_Charon_, _Sarax_).
(Family ?)--*_Graeophonus_.

[Illustration: FIG. 59.--_Schizomus crassicaudatus_, one of the
Pedipalpi. Lateral view of a male. II to VI, the prosomatic
appendages, the first being concealed (see fig. 58); 5, the fifth, and
11, the eleventh tergites of the opisthosoma; pa, the conical
post-anal lobe.

(Original as preceding.)]

_Remarks._--The Pedipalpi are confined to the tropics and warmer
temperate regions of both hemispheres. Fossil forms occur in the
Carboniferous. The small forms known as _Schizomus_ and _Hubbardia_
are of special interest from a morphological point of view. The
Pedipalpi have no poison glands. (Reference to literature (29).)

[Illustration: FIG. 60.--_Liphistius desultor_, Schiodte, one of the
Araneae Mesothelae. Dorsal view. I to VI, the prosomatic appendages;
4, 5, 6, the fourth, fifth and sixth tergites of the opisthosoma.
Between the bases of the sixth pair of limbs and behind the prosomatic
carapace is seen the tergite of the small prae-genital somite.

(Original by Pickard-Cambridge and Pocock.)]

Order 3. Araneae (figs. 60 to 64.).--Prosoma covered with a single
shield and typically furnished with median and lateral eyes of
diplostichous structure, as in the Amblypygi. The sternal surface
wide, continuously chitinized, but with prosternal and metasternal
elements generally distinguishable at the anterior and posterior ends
respectively of the large mesosternurm. Prosternum underlying the
proboscis. Appendages of 1st pair have two segments, as in Pedipalpi,
but are furnished with poison gland, and are retroverts. Appendages of
2nd pair not underlying the mouth, but freely movable and, except in
primitive forms, furnished with a maxillary lobe; the rest of the limb
like the legs, tipped with a single claw and quite unmodified (except
in [symbol: male]). Remaining pairs of appendages similar in form and
function, each tipped with two or three claws. Opisthosoma when
segmented showing the same number of somites as in the Pedipalpi;
usually unsegmented, the prae-genital somite constricted to form the
waist; the appendages of its 3rd and 4th somites retained as spinning
mammillae. Respiratory organs (see fig. 63, _stg_), as i