CHAPTER XVI 
ARACHNIDA EMBOLOBRANCHIATA (CONTINUED )—PALPIGRADI— 
SOLIFUGAE = SOLPUGAE—CHERNETIDEA = PSEUDOSCORPIONES 
Order IV. Palpigradi. 
Minute Arachnids with three-jointed chelate chelicerae, and with 
the last two joints of the cephalothorax free. The abdomen consists 
of eleven segments with a fifteen-jointed flagellum. 
In 1885 Grassi discovered, at Catania, a minute Arachnid which 
did not fall into any of the established orders of Arachnida. 
He named it Koenenia mirabilis. In 1893 Hansen collected 
several specimens in Calabria, near Palmi and Scilla, and care- 
fully redescribed the species in conjunction with Sorensen.’ It 
has been studied still more minutely by Borner.” 
There is a “ head” portion, covered by a carapace, and bearing 
the chelicerae, pedipalpi, and two pairs of legs. The two free 
thoracic segments bear the third and fourth pairs of legs, recalling 
the Schizonotidae (see p. 312), where the portion of the thorax bear- 
ing these legs is separate, though covered by a single dorsal plate. 
There are no eyes, but two hair-structures, believed to be sensory, 
are present on the cephalothorax, and Borner has observed open- 
ings in the second joint of the first pair of legs which have all the 
appearance of “lyriform ” organs, as found in Spiders (see p. 325). 
The last three abdominal segments narrow rapidly, the last 
bearing the anus. A fifteen-jointed caudal flagellum is carried, 
Scorpion-like, above the animal’s back. The body and tail are 
each about a millimetre in length, and the animal is of a trans- 
lucent white colour. 
The mouth is extremely simple, being merely a slit upon a 
slight eminence. There are two sternal plates beneath the 
“head,” and one beneath each free thoracic segment. The 
! Ent. Tidsskr. xviii., 1897, p. 223, pl. iv. 2 Zool. Anz. xxiy., 1901, p. 537. 
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