AMERICAN PAHASmC A RGULID.E— WILSON. 



665 



pendag-es which aro ontirolv waiitinu- in the other two species. These 

 are the temporary inaiulilmlar i);ili)s, which are attached to the sides 

 of the upper lip, and which serve, up to the tirst molt, as the second 

 of th.e two principal locomotor organs. The}^ are made up of two parts, 

 a simple basal portion and a ^-jointed terminal portion bearing at its 

 tip three long plumose seta? similar to those on the second antenna^ in 

 the same species, and, like them, capable of being approximated or 

 separated at pleasure (tig. 5). 



The anterior maxill peds are not moditied in any of the larvie into 

 su,^king disks, but retain instead their primitive form of stout clasping 



Fig. 6.— Antekior max 



organs. They are i-jointed and furnished at the tip with two strong 

 sickle-shaped hooks, placed side by side, the ventral one of which is 

 armed with three sharp barbs on its inner border. These organs are 

 thus similar to the so-called clasping legs of the parasitic Eucopepods 

 (fig 6). 



The posterior maxillipeds are very much smaller than the anterior, 

 and serve as accessory clasping organs, the same function that they 

 perform in the adult. They are o-jointed in all the larva^, and are 

 armed on the inner surfaces of each of the four basal joints with spines, 

 stout setse, or rough papilla?, the kind, number, and arrangement vary- 

 ing considerably in the difl'erent species, but all evidently designed for 



the same purpose. These 

 maxillipeds are terminated 

 ]\v two movable, strongly 

 curved claws, and a rounded 

 knob ending in a sharp 

 spine, knob and claws being 

 placed side ))y side in a line 

 dorso-ventrally, the knob 

 being dorsal. The basal 

 joint is considerably elon- 

 gated longitudinally and bears upon its posterior border a short, stout 

 spine (two in vtegt/lops) in the same place where the spines on the 

 squamiform appendages of the adult subsequently appear (fig. 7). 



-I'OSTEKIIIK MAXILLIPEDOFNEWI.Y HAT(;HEI1 MP 

 I.OPS LARVA SHOWING ARMATURE. 



