POST-LARVAL STAGES OF JASUS LALANDII. 



115 



The third maxillipede is very long, and consists o£ five distinct segments : 

 the first has a gill and spine ; the second has the rudiment oi: an exopodite 

 in the middle of its length, but no division ; the third is shorty the fourth is 

 long and provided with numerous hair-like setse. The third maxillipede of 

 the pueriilus and the adult has seven segments, of which the fourth is the 

 longest, and the proportions are very different from those of this, the oldest 



Fi-. 29. 



Ym. 30. 



First maxillipede of Phyllosoma 

 of 35 mm. 



Second maxilla of Phyllosoma of 35 mm 



phyllosoma procured. Transition stages would probably show a great 

 shortening of the second segment, a division near the proximal end of the 

 third segment, and a very great shortening of the penultimate segment, 

 making seven segments in all. 



The 'pereiopods have well-developed gills (fig. 43, p. 120) — one podobranch 

 with epipodite, one arthrobranch, and two pleurobranchs. The position of 



