596 



CLASS III. MYBIAPODA. 



into a basal (cardo) and peripheral (stipes) part, is without 

 palps and bears at its end teeth (absent in some Geophilidae) 

 and bristles. The 1st maxilla (Fig. 358, MX') consists of a shaft 

 and two blades : the shafts of the two sides are approximated and 

 may be fused. The 2nd maxilla ( MX") consists of a basal piece, 

 which is fused w r ith its fellow to form a lower lip, and of a three- 

 jointed leg-like palp which usually ends in a claw. This pair of ap- 

 pendages, from its resemblance- to the 2nd maxillae of insects, 

 is often called the labium. The maxillipeds or poison-claws 

 (Mf) are the appendages of the first post-cephalic segment (see 

 above). The basal joint of these is (except in Scutigera) fused 

 with the sternal plate of the segment, and the anterior end of 



the plate so formed is often 

 armed w r ith teeth. The 

 rest of the appendage con- 

 sists of four segments, the 

 femur, tibia, and two tar- 

 salia ; the distal tarsal is a 

 sharp claw with the open- 

 ing of the poison gland, 

 which lies in the base of 

 the appendage, at its apex. 

 The tibia and proximal 

 tarsal are, except in Scuti- 

 gera, annular. 



The body-segments fre- 

 quently possess, in addi- 

 tion to the broad tergal 

 and sternal plates, a num- 

 ber of small sclerites in 

 the soft skin of the pleural 

 region. In the Geophilidae 

 (and to a less extent in 

 the Scolopendridae) the 

 tergal and sternal plates 



of most of the segments are partially or completely divided 

 into two, viz. an anterior pretergal plate and a pair of small 

 presternal plates, but the segments never bear more than one 

 pair of appendages each. The legs (see above), like the antennae, 

 tend to vary in length inversely with the length of the body. 



FIG. 358. Mouth parts of Scolopendra mutica (after 

 Stein). Ob Labrum ; Md mandibles ; MX' first 

 maxilla ; MX" 2nd maxilla ; Ta palp ; Mf maxilli- 

 peds (poison claws). 



