48 ARANEIDEA. 
Fam. SCYTODIDZ. 
Tracheal stigmata two, more or less remote from the genital rima. Mandibles 
soldered together at their base. Sternum without sigilla. Calamistrum and cribelluin absent. Spinners 
six, with the colulus more or less well developed or absent. Tarsi with or without an onychium. 
Tarsal claws two or three. Mandibles with the external side striate. Femur of the palpus having one 
or more stridulating-spines on the inner side towards the base. Legs shorter, stouter, and somewhat 
laterigrade in articulation (Sicarius, Lowosceles, and Sicarioides), longer and more slender (Scytodes), 
spinose or clothed with simple fine hairs only. Palpal bulb of male simple, more complex in Diguetia. 
Vulva of female simple, externally consisting of a transverse rima only. 
The family Scytodide includes four very distinct groups of spiders, comprised in the 
subfamilies Sicariine, Loxosceline, Diguetiine, and Scytodine. There seems to be no 
sufficient reason for substituting the name Sicariide for the older name Scytodide, 
which latter has therefore been restored. 
These subfamilies resemble each other in several characters, chiefly in the number of 
eyes and the possession of a stridulating-organ on the mandibles and the femur of the 
palpus. This structure is, however, found also in other groups, notably in Caponina, 
a two-eyed form of the family Caponiide, and in Lepthyphantes, T'meticus, &c., amongst 
the Argiopide (Simon). They resemble each other also in the haustellate formation 
of the mouth-parts, beautifully constructed so that when the apices of the mandibles 
are brought together they form with the apices of the maxille a perfect suctorial 
apparatus, the mandibles being guarded in front of the fang by a soft chitinous piece 
serving to prevent the juices from escaping between the mandibles at their apex in 
front. The simple form of the vulva and that of the palpal organs of the male also 
prove the affinity of these forms. 
The differences between these four subfamilies are very marked, though Sicarius and 
Loxosceles appear to be more closely allied to each other. The latter resembles 
Scytodes in the possession of a tarsal onychium and of a similarly constructed 
stridulating-apparatus, though otherwise, in general form, being much more like 
Sicarius. Diguetia, on the other hand, with its three tarsal claws, resembles 
Scytodes, and with its four femoral stridulating-spines, and in the absence of 
the colulus between the anterior spinners, approaches Sicarius, yet in the absence 
of the mandibular membrane and in the general form of the body differs from 
all three. 
Eyes six. Lung-sacs two. 
Subfam. SICARIZN ZL. 
No colulus between anterior spinners. Anterior row of eyes approximately straight. Lateral eyes wide apart. 
Tarsal claws two, not set on an onychium. Clypeus very high, almost vertical. External side of 
mandible finely striate. Inner side of femur of palpus set with 5 or 6 short stout stridulatory spines. 
Mandibles with a membranous lip on the outer side at the apex. Palpus of female without a claw or 
claw-like appendage at the apex. Anterior margin of maxille not strengthened by a chitinous 
serrula. Carapace compressed. Central thoracic groove shallow and inconspicuous. Body and legs 
clothed with regular rows (or small groups on the body) of longer and shorter spines and bacilliform 
hairs. 
