518 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 88 



Antennae somewhat compressed with a prominent anterior hook,, 

 lateral hook curved back on itself; spine at base of first antennae 

 larger than those at base of second antennae and on ventral surface 

 of lateral hook, postantennal spines still larger, all three very broad ; 

 second antennae long. Suction cups occupying almost full width of 

 carapace; ribs composed of 6 to 10 imbricate plates and an elongate 

 basal segment (fig. 46, h). Second maxillae with two mesial spines 

 of basal plate fairly sharp and short, lateral one broader with the 

 spinous pad extending onto it. Postmaxillary spines very prominent. 



Swimming appendages short, without flagella, very broad dorso- 

 ventrally; first, second, and third progressively longer, fourth short 

 and stout, unmodified except broad coxa on male ; female with bilobed 

 natatory lobe on coxa; precoxa not apparent except natatory lobes,, 

 which are prominent and extend posteriorly in the male. 



Slight concavity on coxa of second swimming appendages with 

 minute spines around the edge. The socket is a large rounded con- 

 cavity on the coxa of the third appendages that fits over a swollen 

 anterior surface of the coxa on the fourth leg rather than being a 

 true peg. The precoxa is indicated by a somewhat triangular swim- 

 ming lobe closely attached behind the abdomen (fig. 46, c). 



Taken on the needlefish {Strongylv/ra notata) and sand bream 

 {ArchosarguB unifnaculatus) in Lemon Bay, on the Gulf coast of 

 Florida. 



ARGULUS FUSCUS Bere 



Figure 47 



Argulus fnscus Beke, 1936, p. 578, pi. 1, figs. 2-10. 



Carapace elongate, lateral sinuses shallow, cephalic area well 

 marked ; carapace reaching onto abdomen ; posterior sinus about one- 

 fourth its length, very narrow. Anterior respiratory area oblong, 

 posterior one considerably wider and flaring to double the width of 

 the anterior portion about halfway back (fig. 47, a). In the male the 

 abdomen is about one-third the total length, somewhat rectangular 

 in shape, sinus shallow, sides flaring, anal furcae basal, testes very 

 long, reaching sinus; abdomen oblong in female, with smus reaching 

 over half its length. 



Antennae with a prominent anterior hook, tip of lateral hook 

 curved back on itself, flagellum of first and second antennae extend- 

 ing beyond lateral hook, which is short. Ventral spine prominent, 

 basal spines of first and second antennae much smaller than post- 

 antennal spines. Suction cups with ribs composed of 6 or 7 imbricate- 

 plates and a rectangular segment (fig. 47, b) in male and 12 to 14 in 

 'female, with the basal segment almost square. Second maxilla© 



