436 CBFSTACEA. 



them still swim freely, but most of them live on the gills, in the 

 pharynx, and on the outer skin of fishes. Some live within the 

 tissues of their host (Penella), and nourish themselves on the blood 

 and juices of the latter. 



Fam. Corycaeidse. Anterior antcnnse short, few jointed, and similar in both 

 sexes. The posterior antennae unbranched, with clasping hooks, usually differ- 

 ent according to the sex. Mouth parts often arranged for piercing. Median 

 eye and lateral eyes often present. They live partly as temporary parasites. 

 Coryctsus elongatus Cls., Sappliirina fulgens Thomps. 



Fam. Chondracantliidae. Body elongated, often without distinct segmenta- 

 tion, and furnished with pointed outgrowths. Abdomen stump-like. The two 

 anterior pair of swimming feet are represented by bifid lobes, the others are 

 wanting. There is no suctorial proboscis, the mandibles are sickle-shaped. The 

 pear-shaped males are small and dwarfed, and attached, often in pairs, to the 

 body of the female. Chondracanthm gibbosns Kr. (on Lophius). Ch. cornutus 

 O. Fr. Mull., on flat fish (Pleuroncctidce) (fig. 345). 



Fam. Caligidas. Body flat, with shield-like cepkalothorax, and very large 

 genital segment which in the female is especially swollen. Abdomen, on 

 the contrary, is small and more or less reduced. There is a suctorial tube and 

 styliform mandibles. Four paired biramous swimming feet enable the animal 

 to swim rapidly. They live on the gills and the skin of marine fish, and the 

 females have long string-like egg tubes. Caligus rapav Edw., Cccrops Latreillil 

 Leach. 



Fam. Lernaeidse. The body of the female vermiform or rod-shaped ; unseg- 

 mented, with outgrowths and processes on the head. Mouth parts piercing 

 with suctorial tube. There are four pairs of small swimming feet. The females 

 become attached to fishes, in which the anterior part of their body is buried. 

 Lcrnceocera cyprinacea L., Penella sagitta L., Lerncea brancMalis L. 

 (fig. 346). 



Fam. Lernaeopodidae. Body separated into head and thorax, abdomen 

 rudimentary. Mouth parts piercing with suctorial tube. The external maxilli- 

 peds attain a considerable size, and in the female unite at their points so as to 

 form a single organ of attachment, by means of which the animal adheres 

 permanently. Swimming feet completely absent. The males, which are more 

 or less dwarfed, have large free clasping feet, and are, like the females, without 

 swimming feet. Aclitliercs percarum Nordm. (fig. 344). Ancliorella uncinata 

 0. Fr. Mull, (on species of Gadus). 



2. Sub-order: Branchiura.* 



Carp-lice. With large compound eyes, and long protrusible spine 

 in front of the suctorial tube of the mouth ; with four pairs of elon- 

 gated biramous swimming feet. 



zerkrebse," Nova acta Ac. Cces. Leop., Tom XVII., 1835. C. Glaus, " Ueber den 

 Bau und die Entwickelung von Achtheres percarum," Zeitschr fiir wisx. Zool., 

 1861. C. Glaus, " Beobachtungen iiber Lernaeocera, etc., Marburg, 1868. 



* Jurine, " Memoire sur 1'Argule foliace," Annales du Museum d'hist. 

 nat., Tom. VII., 1806. Fr. Leydig, " Ueber Argulus foliaceus," Zeitsclirfilr n-iss. 

 Zool., Tom II., 1850. E. Cornalia, " Sopra una nuova specie di crostacei sifonos- 

 tomi," Milano, 1860. C. Glaus, " Ueber die Entwickelung, Organization und 

 systematische Stellung der Arguliden," Zeitsclirfiirrviss. Zool., Tom XXV., 1875. 



