COMPAEATIVE MOEFHOLOGY OF THE GALEODID^. 323 



the clieliceraj, say, of the Aviculariidai or Pedipalpi; (3) a longitudinal section through the chelicera of 

 Phrynus (PI. XXIX. fig. 2) shows a distinct sclerite {j) where such a sclcrite might be found if a joint 

 had disappeared at that spot. Further investigations, however, are necessary. In the meautime I put 

 forward the above suggestion as an alternative to the highly improbable assumjjtion that any limb could 

 rotate through 180°. 



Ou the inner sides of the chelicerae, thick rows of feathered setce, running longitudinally 

 along the digits, serve to conduct the juices of victims towards the mouth {cf. p. 357). 

 These setae give a very hairy character to the cheliceraj, and though the hairs end 

 towards the hard red points of the digits, the pores of vanished hairs can be seen 

 traversing the chitin right to the tips. 



The Reputed Foisoiwus Character of the Bite. — There being no specialized poison- 

 glands, I would suggest that to the exudation through these pores is due the dangerously 

 poisonous character which is attributed by nearly all writers, both ancient and modern, 

 to the bite of this animal *. I do not think that this almost universal testimony can be 

 refuted without actual experiment. Unlike the Spiders, whose needle-like jaws can 

 convey the venom from poison-bags with muscular walls into the slightest wound, the 

 Galeodidse must bite through the skin and plimge the tips of their pincers into the 

 soft tissues before the jjoison takes effect. This is in accord with all the ancient accounts 

 that only the tenderest parts of the body are bitten. 



If this suggested origin of the poisonous effect of the bite of Galeodes from the exudation through open 

 setal pores prove correct, it is not without interest for the morphologist. PI. XXIX. fig. 2 shows the tip 

 of the movable digit of Phrynus, with a special bunch of setae on its outer edge. In the Pseudoscorpious 

 these are absent, but are rejilaeed by a series of tubes leading into specialized spinning-glands. In the 

 Spiders these setae are also absent, but there is one large poison-gland opening also practically on the 

 same spot, while in Galeodes there are no setae at the tip of the digit, but a great number of setal pores 

 presumably exuding poisonous matter without any special gland formation. The bearing of this upon 

 the probability of the origin of both spinning- and poison-glands from setiparous glands is obvious (see 

 further, pp. 376 and 383). 



The Flac/eltum. — The chelicerae, in the Galeodidce, are provided with remarkable sensory 

 fiagella (i. e. highly specialized sette) which vary greatly in shape in the different genera 

 (PL XXVII. fig. 11). It is not certain that these are contiued to the male alone, as was 

 once thought. The true explanation of the inconstancy of their appearance I have not 

 been able to ascertain. The chelicerae are said to be much smaller in the males than in 

 the females. 



The extraordinary combs on the fixed digits of the chelicerje in the Pseudoscorpious may be homologous 

 with these fiagella ; they stand out at about the same spot, and in both cases are associated with a 

 tuft of feathered setae. The combs, however, are not formed like true setae, but, as is easily seen iu 

 transverse sections, are folds (apparently rigid) of the hard outer glassy layer of the chitin; they are 

 therefore extremely thin and transparent. 



The Ped'q)cil])s. — While the cheliceraj have folded together over the mouth so as 

 to lie parallel to the median Une, the coxte of the pedipalps make an angle with the 

 median line slightly less than 45°, the beak being wedged in between them (PI. XXVIII. 



* Cf. the accounts given by Lichtenstein and Herbst, and by Dufour. 



43* 



