C »AI>, IX. 
CRUSTACEANS. 
329 
their diel® ; so that of the former, those which were best 
able to find the female, and of the latter, those which were 
test able to hold her when found, 
have left the greater number of 
progeny to inherit their respec- 
tive advantages. 4 
In some of the lower crusta- 
ceans, the right-hand anterior 
a *>tenna of the male differs 
greatly in structure from the 
left-hand one, the latter re- 
sembling in its simple tapering 
joints the antennae of the fe- 
male. In the male the modi- 
fied antenna is either swollen 
in the middle or angularly bent, 
°r converted (tig. 3) into an 
degant, and sometimes wonder- 
fully complex, prehensile organ. 5 
If serves, as I hear from Sir J. 
Lubbock, to hold the female, 
a ud for this same purpose one 
°f the two posterior legs (b) ou 
the same side of the body is 
converted into a forceps. In 
a Uother family the inferior or 
posterior antennae are “ curiously zigzagged in the 
^ules alone. 
4 ‘ Facts and Arguments for Darwin,’ English Iranslat. 1869, p. 20. 
the previous discussion on the olfactory threads. Sara has de- 
bribed a somewhat analogous case (as quoted in ‘Nature, 18/0, 
It 455) in a Norwegian crustacean, the Pontoporcia affinis. 
5 See Sir J. Lubbock in ‘Annals, and Mag. of Nat. Hist.’ vol. xi. 
J 85 3, pi. i. ail d x. ; and vol. xii. (1853) pi. vii. _ See also Lubbock in 
transact. Ent. Soc.’ vol. iv. new series, 18oG-1858, p. 8. "W itli respect 
^ tlie zigzagged antennse mentioned below, see Fritz Muller, ‘Facts 
a nd Arguments for Darwin ’ 1869, p. 40, foot-note. 
a 
Fig. 3. Labidocera Darwini! (from 
Lubbock). 
a. Part of rigbt-band anterior an- 
tenna of male, forming a pre- 
hensile organ. 
b. Posterior pair of thoracic legs of 
male. 
c. Ditto of female. 
