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homologous with the retractile organ discovered by 
Dufour, in Solifugæ, if an homology is existing it must 
be with the interior sense-organs discovered by Gaubert 
and Bertkau; this homology, however, appears as vet 
very questionable to me, on account of the oceurrence 
of a fine row of hairs in Phrynus (see a few more 
remarks on this subject under Solifuge). 
Bruce writes 1886 (op. cit. p. 47): »On the coxal 
joint of the fourth appendage [2d pair of legs| a sense- 
organ was very conspicuous in the young pedipalp. The 
hypodermic cells of that joint become columnar, unlike 
other hypodermic cells, which are of irregular contour. 
These elongated cells are continued externally to form 
filaments, several of which enter a single pair, which 
isthe external part ai the sense-organ.« — I have 
not seen nor searched for this organ, but I have thought 
it convenient to copy the whole description; for the 
rest the entire note seems to me to be immature. 
D. Systematic. 
The first attempt, worth mentioning, of a classifica- 
tion of Phrynide in strictly limited genera is owing 
to F. Karsch (op. cit.) but, strange to say, he has but 
found and made use of one single character, viz., the 
numbers of the joints in the hindmost tibia. In the 
year 1889 Thorell (op. cit.) draws attention to several 
new characters; I shall point out the division of the 
claw of the palpi in 2 joints in some of the forms, and 
above all, the occurrence of arolium on the apex of 
the tarsus of the 3 posterior pairs of legs in Charon 
and Catageus in opposition to its absence in other 
genera; in the description of the species he mentions 
that 5 joints are found in the tarsus of Catageus and 
Charon, 4 in Phrynus Goésii Thor., but he does not 
use this excellent feature as a character for genera. — 
