Spiders and Their Near Relatives 



is commonly termed the trocbantin by writers on the Pseudo- 

 scorpionida. But the word trochantin was first used in this sense 



by Blanchard in 1852, long after 

 it had been in general use by 

 entomologists in an entirely dif- 

 ferent sense. 



The number of segments in 



LEGS OF CHELIFER 

 a, fore leg b, hind leg i, coxa 2, trochanter 3a, second 

 trochanter 3b, femur 4, tibia 



the tarsus varies from one to three. The praetarsus is usually 

 distinct; and there are two tarsal claws. Below the claws 

 there is a membranous empodium (Fig. 46). 



The respiratory organs are tubular tracheae, which open 

 by two pairs of long slit-like spiracles on the second and third 

 abdominal segments, on the ventral side near the lateral margins. 

 In addition to these there are vestigial spiracles on all of the re- 

 maining abdominal segments (Bernard '93). In the form of the 



respiratory organs the pseudo- 

 scorpions differ greatly from the 

 scorpions, near which they are 

 commonly placed in the text-books. 

 The opening of the reproduc- 

 tive organs is on the middle line 

 between the second and third ab- 

 dominal sterna. The female carries 

 the eggs about, attached to the abdomen; they are on the 

 outer surface of a sac which is attached to the wall of the opening 

 of the reproductive organs by a slender and broad pedicel, the 

 whole forming a small raspberry-shaped mass. The sac is filled 

 with food material; and the young when hatched are furnished 

 with a long sucking beak by means of which they obtain the food 

 thus supplied. They attain their definite form in this position. 



Fig. 46. TARSUS OF CHELIFER 



42 



