180 
that is to say on representatives for 3 genera very 
divergent from each other, and they are, in all proba- 
bility, found in all forms of the order. The organ on 
the lower side of the Ist joint appears always to 
be in the same place; the depression on the lower 
margin of the 2d joint is, on the contrary, sometimes 
changing its position to the inner side of the lower 
edge (Galeodes). 
B. Other Sense-Organs. 
Gaubert and shortly after Bertkau (see Gaubert op. 
cit.) have described remarkable sense-organs in the 
interior of the apical part of the palpus and of the Ist 
pair of legs. I have not myself examined these organs, 
but I am mentioning them here, partly for the sake of 
completeness, partly because Bernard (op. cit. p. 29) 
mentions the protrusible organ discovered by Dufour on 
the apex of the palpi, and according to his own state- 
ment he wishes to follow C. Koch and believes it to 
be »asensory organ, probably olfactory«, without having, 
however, been acquainted with Gaubert’s preliminary 
communication and later work (see Gaubert p. 151—52) 
and not in the slightest calling attention to the existence 
of the organs placed at the side of the protrusible 
organ. | have examined the protrusible organ more 
closely, but I have not been able to understand it. Its 
movements ought to be observed and studied on living 
animals. It is, undoubtedly, a kind of fixing cup, and, 
as stated by Gaubert (op. cit. p. 152), »il est incon- 
testable qu’elle ne sert au Galeode que pour s’accrocher 
ou grimper.« The terminal face of the palpi is showing 
great difference as to structure f. ex. in Solpuga and 
in Rhax, and I look upon it as most likely that beautiful 
