COPEPODA. 407 



maxillipeds are symmetrically modified as prehensile organs, the latter 

 especially in the male. Heart absent. The lateral elements of the 

 eye are often large. The openings of the oviducts are dorsal 

 or lateral. Egg sacks paired. Lubbockia Claus ; Oncaea Philippi ; 

 Corycaeus Dana. Copilia Dana, bodies of glass-like transparency ; 

 strongly marked sexual dimorphism ; female cylindrical, male 

 flattened; C. vitraea Haeckel, in the female (II. 1)* the thoracic 

 appendages bear broad plumose setae which, like the stomach, are of a 

 bright orange colour, and the lateral elements of the eyes have large 

 lenses ; the male (L. 8) * is colourless and without lateral eyes. 

 Pachysoma Claus. Sapphirina J. V. Thompson. Lateral elements of 

 the eyes with cuticular lenses present in both sexes, male much broader 

 than female and brilliantly iridescent (I. 7).* Sapphirinella Claus. 



Fam. 10. Ergasilidae. Copepods in which the females though retaining 

 the power of swimming are parasitic on the gills of fishes and the bodies of 

 mollusca, annelids, etc. The males are probably free at any rate during 

 part of their life. Body cylindrical or flattened, segmented. Anterior 

 antennae 5-7-jointed, postr. antennae modified as grappling hooks, 

 maxillipeds prehensile. The mouth parts are riot modified into a sucking 

 tube, and the eye is simple and median. Egg sacks paired. Doridicola 

 Leyd., parasitic on Doris. Sepicola Claus, on squids. Eolidicola Sars. 

 Lichomolgus Thor. in branchial sacks of tunicates. Terebellicola Sars, on 

 Terebellidae. Eucanthus Glaus. Bomolochus Nordm., on pleuronectid 

 fishes. Ergasilus Nordm. on teleostean fishes. Thersites Pagenst. 



Fam. 11. Ascomyzontidae (Asterocheridae). Structure and mode of 

 life resembling that of the Ergasilidae, but the lips are modified into a 

 suctorial apparatus containing the styliform mandibles. Anterior 

 antennae 5-'20-jointed, geniculated in the c? , ant", mx" and mxped 

 prehensile. The eye may be absent. Nicothoe Aud., N. astaci with a 

 discoidal proboscis ; lives on the gills of the lobster. Asterocheres Boeck 

 (Ascomyzon Thor.) with a long sucking tube, on tunicates, sponges and 

 echinoderms. Dyspontius Thor., Artotrogus Boeck, and many others. 



Fourth series (Fams. 12-14). 



Fam. 12. Caligidae. Both sexes live as parasites on the skins of 

 fishes, but are able to swim rapidly. They are broad flattened Copepods 

 of comparatively large size and incompletely segmented. There is a 

 shield-like cephalothorax and the free thoracic segments are often pro- 

 duced into lateral lobes. The genital segment is swollen, especially in 

 the female, and the rest of the abdomen reduced. Anterior antennae 

 short, with 2 or 3 free segments ; the basal segment fused with the margin 

 of the cephalothorax. Posterior antennae reduced to a grappling hook, 

 not projecting beyond the margin of cephalothorax. Mandibles styliform, 

 enclosed in a sucking tube. First maxillae free, second maxillae and 

 maxillipeds modified as hooks. 4 pairs of usually biramous swimming 

 feet are present, the 5th pair being often rudimentary or absent. Heart pro- 

 vided with paired valves. Eye, when present, simple and median, or with 

 paired elements. Egg sacks paired and elongated. Hermilius Hell., Para - 

 petalus Stp.Ltk., Synestius Stp. Ltk., Caligodes Hell., Caligus Mull., Lepeoph- 



* These numbers refer to the plates and figures in Giesbrecht's Mono- 

 graph on Pelagic Copepods, Fauna and Flora of the Gulf of Naples, vol. 19. 



