THE CRUSTACEA OF NEW JERSEY. 95 



Female. — Carapace orbicular, strongly arched, frontal plates 

 more or less completely fused with carapace and not distinct, and 

 grooving- similar to that in Pandarince. Three free thorax seg- 

 ments, first two usually fused and furnished with a single pair 

 each of dorsal plates and lateral lobes. Third segment carries 

 pair of enlarged dorsal plates which cover front portion of 

 genital segment. Latter large as, or larger, than carapace and 

 with pair of dorsal plates which entirely cover this segment as 

 well as abdomen. Abdomen one-jointed, with large anal laminae 

 armed with spines instead of setae. Abdomen sometimes with 

 broad wings extending to lateral margins of genital segment, 

 when egg-strings are concealed below genital segment, or some- 

 times without wings, when egg-strings long, straight and visible 

 as in Pmidarincu. First antennas usually two-jointed, rarely 

 three- jointed. Second maxillipeds with terminal claws. All legs 

 biramose, rami of first three pairs two-jointed, of fourth pair one- 

 jointed and usually enlarged into broad lamellae, armed only 

 with spines. 



Male. — A fixed form incapable of locomotion like female. 

 Carapace and thorax segments similar to female, dorsal plates of 

 fourth segment being reduced in size. Genital segment also 

 much smaller, with abdomen partially visible beyond its hind 

 margin. Abdomen without wings in all genera. Second anten- 

 nas and second maxillipeds with stout prehensile claws. All feet 

 biramose, rami as in female, except those of fourth pair rarely 

 much enlarged. Rami of first three pairs with plumose setae in 

 a few genera, fourth pair and all rami in other genera without 

 them. 



Chalinius. — Attached by two broad ribbon-like frontal fila- 

 ments very short and parallel. 



Remarks. — The parasites of this sub- family are found largely 

 on the Ocean sun-fishes (Molidcu), though they also sometimes 

 occur on tunnies, porcupine-fishes, flat-fish, sharks, etc. The fol- 

 lowing, compiled from Dr. C. B. Wilson, discusses their ecology: 

 These parasites are more gregarious than the PandarincB and are 

 found in bunches of fifteen to thirty or more, attached to the 

 outside skin and gills of fish. The combined laceration of their 



