SUPER-ORDER PSEUDOSCORPIONES. Differing from the Caulogastra in the absence of a "waist" the large size of the dorsal plate of the pregenital somite, the absence of spiracles on the first abdom inal somite, the presence in the cephalothorax of silk glands open ing upon the mandibles, which are provided with a special organ, the serrula, for manipulating the silk.
Order Chelonethi. Carapace unsegmented. Mandibles two jointed, chelate. Palpi very large and chelate, their basal seg ments and those of the four pairs of legs meeting in the middle line and replacing the sterna. Abdomen sometimes with I r freely jointed somites, second and third with a pair of spiracles.
ments free. Mandibles two jointed, powerful and chelate. Palpi pediform and tactile, their basal segments fixed, dissociated from the mouth which is at the apex of a porrect proboscis. Legs with their basal segments fused across the middle, replacing the sterna. Abdomen with ten somites, the second, third and sometimes the fourth with ventral spiracles. Intromittent organs of the male situated on the mandibles.
Families Galeodidae (Galeodes), Solpugidae (Solpuga). The Solifugae, mostly large active, rapacious Arachnida, are found in the warmer parts of the eastern and western hemispheres. They are a very distinct group, showing some resemblances to the Palpigrada.