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allow any specific interpretation as to its origin. 
If the maxillipeds are the first pair of thoracic 
appendages, the sternal furca may be the rem- 
nant of the sternal plate which exists between 
the first three pairs of thoracic legs of L. dis- 
simulate and many other caligoids. No defini- 
tive evidence for this idea can be offered, how- 
ever, other than the relative position to the 
maxillipeds and the presence of sternal plates 
on some of the thoracic legs. Futhermore, the 
sternal furca in L. dissimulatus does not appear 
until the fourth chalimus, long after the maxil- 
lipeds, the thoracic legs, and the sternal plates 
of the first two thoracic legs. The hypothesis 
has, therefore, at least one pitfall unless, and no 
information is given to support this, a shift can 
Fig. 18. Sternal furcae and first thoracic legs of developmental stages of L. dissimulatus. a-e, Sternal fur- 
cae: a, Third chalimus; h, fourth chalimus; c, fifth chalimus; d, sixth chalimus; e, adult, f-m, First thoracic 
legs: f, Copepodite; g, first chalimus; h, second chalimus; i, third chalimus; j, fourth chalimus; k, fifth chalimus; 
l, sixth chalimus; m, adult. 
