96 REPORT OF NEW JERSEY STATE MUSEUM. 



claws often produces a large pit or sore, in the bottom of which 

 they cling tightly. Nothing of this sort is found among the 

 PandarincE, as they do not collect in such numbers and cling 

 partly, if not chiefly, by means of their adhesion pads. Hence 

 when several of them get together, as often happens on a shark's 

 fin, there is very little laceration and no bunch or sore is formed. 

 The abrupt transition and the consequent degenerate character of 

 the male forms one of the chief characteristics of the group. The 

 only locomotion possible to either sex is such as can be accom- 

 plished by loosening one set of prehensile organs and obtaining a 

 new hold by stretching the body, while still keeping a second set 

 securely fastened. When once placed, with the second antennss 

 buried in the flesh of the host, it is probable that the female does 

 not subsequently change her position. The male is usually found 

 attached to the female, the front margin of its carapace burrowed 

 beneath the apron of her third swimming-legs, and its second 

 antennae clasped around her fourth thorax segment. When he 

 has once gained this position the male probably does not change 

 it during life. The organs of prehension are similar to those in 

 the PandarincE. The chief hold is maintained by the second an- 

 tennae, which are buried for their entire length in the skin and 

 underlying flesh of their host. During life the body of the 

 copepod frequently trails off in the water, with no attachment 

 to the host except these antennae, which gives it the appearance 

 of being fastened by a frontal filament. Usually, however, the 

 antennae are reenforced by the second maxillipeds and adhesion 

 pads. The latter are similar to those in the Pandarincc, but there 

 are two of them behind each first antenna, while there is none 

 on the base of the second pair. These parasites certainly never 

 drop off into the boat or anywhere else, as claimed for the genera 

 in the PandarincE. Both the antennae and maxillipeds are set 

 so firmly in position that they cannot be loosened without break- 

 ing them. Even after the death of the parasite it is usually 

 necessary to cut around these appendages if one would remove 

 the entire animal. When placed alive in the aquarium they are 

 more helpless than the PandarincE, and both sexes can only lie 

 in the place they are put, with an occasional weak and spasmodic 



