94 REPORT OF NEW JERSEY STATE MUSEUM. 



Painily CALIGID.E. 



Carapace broad and usually depressed. Cephalothorax incom- 

 pletely segmented, free thoracic segments often partially over- 

 lapped or hidden by dorsal plates. Anterior antennae short, club- 

 shaped, with two or three free joints, their basal seg"ments an- 

 chylosed with anterior border of carapace. Posterior antennae 

 in form of simple hooked claw, not extending beyond carapace. 

 Mouth in form of more or less elongated suctorial beak, formed 

 out of upper and under lips and inclosing toothed mandibles. 

 Maxillae free, both pairs rudimentary, and first pair sometimes 

 wanting. Maxillipeds also free, in form of hooked claws, first 

 pair weak, second much stronger and used for prehension. First 

 four pairs of thoracic legs usually biramose, but first and 

 fourth pairs frequently uniramose, and fifth pair rudimentary, 

 often invisible dorsally or entirely wanting. Two simple eyes 

 fused on median line often wanting. Generative organs paired in 

 both sexes. Females with two cord-like egg tubes, usually quite 

 long. Eggs in a single row. Male usually smaller than female, 

 and both sexes permanent parasites on fishes. 



Key to the mih -families. 



a. First thoracic segment only fused with head, others free ; one or more of 

 them with paired dorsal plates; all four pairs of legs biramose. 

 b. Frontal plates fused with carapace ; egg-cases convoluted, entirely 

 hidden. cecropin.b 



hh. Frontal plates distinct ; egg-cases visible their entire length. 



PANDARIN.E 



aa. Three anterior segments of thorax fused with head; fourth and genital 

 segments free, and former without dorsal plates or any appendages ex- 

 cept fourth legs. . caugin.^ 



Siih-Family Ckcropin.^. 



First thorax segment fused with head, and second and third 

 segments more or less fused inter se. Fourth segment with pair 

 of dorsal plates in both sexes, overlapping genital segment. 

 Sexes very similar. 



