CHAPTER XVII 



AKACHNIDA EMBOLOBRANCHIATA (CONTINUED} - - PODOGONA- 

 PHALANGIDEA = OPILIONES HABITS STKUCTUKE CLASSIFI- 

 CATION 



Order VII. Podogona (Ricinulei). 



Tracheate Arachnids with tivo-jointed chelate chelicerae and 

 prehensile pedipalpi. Tlie tarsus of the third leg of the male bears 

 a copulatory organ. 



IN 1838 Guerin-Meneville * described an Arachnid from 

 West Africa which he named Cryptostemma westermannii. At 

 rare intervals occasional specimens of allied forms have been 

 taken in the same region until 

 six species of Cryptostemma have 

 been established. In South 

 America, also, two unique ex- 

 ;i 11 1] ilcs of very similar creatures 

 are the only known representa- 

 tives of the two species of the 

 allied genus CryptocM-n*. All 

 the examples hitherto found are 

 of fair sixe (between 1 inch and 

 1 inc.h in length), and bear some 

 general, though superficial, resem- 

 blance to the Trogulidae, which 

 lias led to their being placed 

 among the l'halangide;i hy almost 

 all the Arachnologists who have 

 noticed them. Their claim to this systematic position, however, 

 is extremely doubtful, and I [arisen and Sorensen, who have had 

 the opportunity of studying the group much move minutely 

 1 Rewie Zoologique par la Soci&4 Cvwieneime, \>. 1". 



439 



Kiu. JJS. 



x 4. 



( utrr I l.ni ien ami Sorensen. ) 



