COPEPODA. 409 



cephalo thorax, the mouth parts suctorial, small hooked maxillipeds and 

 four pairs of small swimming feet. The genital segment of the female is 

 much elongated and the hind part of the body is unsegmented. A median 

 eye is present throughout life. The development of the male ceases at 

 this stage, but after fertilization the body of the female increases 

 enormously in size, growing worm-like, while the anterior part is buried 

 in the tissues of the animal on which it is parasitic (Fig. 266 c, d). 

 The region in front of the genital segment is, in many genera, con- 

 stricted, and the eggs sacs are either oval or much elongated, being 

 in the latter case straight or thrown into a closely packed spiral. 

 Lernaeocera Blainv., Therodamas Kr., Peniculus Nordm. Pennella Oken., 

 P. sagitta, L. The female lives nearly buried in the flesh of the 

 pelagic fish Antennarius, only the posterior part of the body carrying 

 the straight egg tubes and beset on either side with a series of long pro- 

 cesses (respiratory ?) projecting beyond the body of the host ; two long 

 backward pointing processes from the sides of the thoracic region anchor 

 it in position. P. filosa L. attains a length of 6-7 inches. Lernaeonema 

 Edw., Lerneaenicus Les., Echetus Kr., Lophura Koll., Lernaeolophus Hell., 

 Lernaea L (Fig. 266). The females are parasitic on the gills of fishes 

 (rarely on tunicates). The genital segment is swollen, ventricose and 

 S-shaped. Rootlike processes extend from the head into the ulcerated 

 tissues of the branchial arches in which it is embedded. The males re- 

 main small and lead a free life. Haemobaphes Stp. Ltk., Peroderma Hell., 

 Nadbranchia Hesse, and (?) Pseudulus Nordm. 



Fifth series (Fams. 15-16). 



Fam. 15. Chondracanthidae. The males and females ^differ much 

 in form and size. The females are comparatively large animals attached 

 to the gills or other soft parts of the skin of fishes. The abdomen is 

 stump-like and the body produced into stout irregular processes (in which 

 lobes of the ovaries may be lodged) giving it a monstrous misshapen ap- 

 pearance. There is no suctorial proboscis and the mandibles are sickle 

 shaped. Maxillipeds small and hooked. The swimming feet are reduced 

 to two pairs of bifid lobes. Egg sacs elongated or saccular. The dwarf 

 males are found attached to the body of the female. In them the cephalo- 

 thorax is arched dorsally and the abdomen conical and segmented. 

 Lesteira Kr., Medesicaste Kr., Strdbax Nordm., Trichthacerus Kr., Blias 

 Kr., Chondr acanthus la Roche (Fig. 265), Splanchnotrophus Hanc., Diocus 

 Kr., Ismailia Bergh., Tanypleurus Stp. Ltk. 



Fam. 16. Lernaeopodidae. As in the last family there is marked 

 sexual dimorphism. The bodies of the females are large and unsegmented. 

 Maxillipeds in some genera short and thick and in some cases completely 

 fused together, but generally long and arm-like and only united at their 

 ends in a single horny disc, common to both, by which the animal is 

 attached to the host (Fig. 264). The toothed mandibles are contained in 

 a suctorial proboscis. The swimming feet have completely disappeared. 

 Egg sacks paired and saccular. The males resemble those of the Chon- 

 dracanthidae in shape, but the abdomen is unsegmented, the mouth begins 

 in a suctorial tube, and both second maxillae and maxillipeds are strongly 

 hooked. They are attached to the bodies of the females. Thysanote 

 Kr., Basanistes Nordm., Varibenedenia Malm., Charopinus Kr., Achtheres 

 Nordm., Lernaeopoda Kr., Tracheliastes Nordm., Brachiella Cuv. ; Anchor- 

 ella Cuv., on the gills and mouth parts of fishes (?) Herpyllobius Stp. Ltk. 



