512 PROCEEDINGS OF THE NATIONAL MUSEUM vol.88 



Suction cups supported by a series of seven to nine short rods becom- 

 ing progressively smaller toward the edge of the rim, distal ones with 

 only one side of rod thickened giving a C-shap©d effect (fig. 42, c)^ 

 Second maxillae stout, basal plate broad with three (sometimes two or 

 four) broad stout teeth on the edge, lateral tooth stouter than others ; 

 the usual two pairs of postmaxillary spines absent. 



The swimming appendages have flagella. Female with a flat lamella 

 on the basis of the fourth appendages and a somewhat boot-shaped 

 lamella on the coxa. There is a slight widening of the coxa of the 

 third appendage to form a posterior ridge. 



Second appendage of male has the usual posterior armored pad on 

 coxa, which is peculiar in that it is highest on the distal end of the coxa 

 and forms a saddle to fit over the next appendage. The third append- 

 age has a flap on the anterior distal edge of the coxa extending over 

 the basis to the exopod (fig. 42, b). From the posterior of the same 

 segment extends a battle-ax-shaped flap over the fourth appendage 

 and laterally over the basis covering the lobe containing the socket. 

 The exopod has a knee at the base. The fourth appendage has the 

 usual peg with a small prolongation to form the tip which is some- 

 what enlarged with a ridge around the base. The posterior surface 

 of the coxa is prolonged into a boot-shaped flap. 



This species has been taken on carp {Cyprinus carpio) at Fairbury, 

 111. ; from Erlmyson sucetta ohlongus at Warren, Mass. ; Oatostonius 

 commersonii at New Haven, Conn., Woods Hole, Mass., and Lake 

 Champlain and Oneida Lake, N. Y. ; and on C. commersonii, G. nigri- 

 cans, and G. catostomus in Lake Maxinkuckee, Ind. In Connecticut 

 and Massachusetts it was found in brackish water, but in fresh water 

 elsewhere. 



ARGULUS APPENDICULOSUS Wilson 



Figure 43 



Argulus appendiculosus Wilson, 1907, p. 419, pi. 32, figs. 23-30. 

 Argulus Mramosus Bebe, 1931, p. 428, figs. 1-7. 



Carapace slightly longer than wide, reaching abdomen in male^ 

 shorter on female; cephalic area not prominent. Abdomen spindle- 

 shaped, lobes pointed; anal furcae almost basal, diverging laterally 

 and truncated; sinus about half the length of the abdomen. The 

 respiratory areas consist of a small mesial rounded one fitted into a 

 notch in the larger lateral one (fig. 43, &) . The male has been reported 

 up to about 10 mm. in length and the female considerably larger. 



First antennae with no anterior knob, no spine on ventral median 

 surface or at base; flagellum biramous. Second antennae with no 

 spine at base, spine near midline long and blunt, flagellum well sup- 



