AMPHIPODA. 455 



passages in mud. Cerapus tubularis Say., lives in tubes. Pvdocerus variegatus 

 Leach., English coast. Chelura, terebrans Phil, is allied here, gnaws, with 

 Liminorla lignorum, wood-work in the sea. North Sea and Mediterranean. 



Fam. Orchestiidae. Anterior antennae usually short, always without accessory 

 ramus. The posterior pair of uropoda are unbranched and are shorter than 

 the preceding pairs. They live on the shore, especially on sandy beaches, and 

 move by springing. Talitrns saltator Mont. = T. locusta Latr. On the sandy 

 coasts of Europe. Orcliestla littorea Mont., North Sea. 



Fam. Gammaridae. The anterior antennas often have a second ramus, which 

 is always longer than the shaft of the posterior. The coxal plates of the four 

 anterior pairs of legs are very broad. They move more by swimming than by 

 springing. Gammarus pulex L., G.fluviatilis Eos., G. marinas Leach. In the 

 blind Niphargus Schiodte the crystalline cones and eye pigment are wanting. 

 N. puteaniis Koch., in deep springs and lakes (Lake of Geneva). Lysianasia 

 Costa Edw., Mediterranean. L. atlantica Edw. L. magellanica Lillj. 



Tribe 3. Hyperina. 



Amphipoda with large swollen head and large eyes, usually divided 

 into frontal and lateral eyes. They have a pair of rudimentary 

 maxillipeds functioning as underlip. 



The antennae are sometimes short and rudimentary, sometimes of 

 considerable size, and in the male are elongated into a multiarticulate 

 flagellum (Hyperidce). The posterior antennae may in the female be 

 reduced to the basal joint enclosing the glandular tube (Phromina) ; 

 in the male, on the contrary, they are folded in a zigzag, after the 

 manner of a carpenter's rule (Platyscelince). A paired auditory 

 vesicle may be present above the brain (Oxycephalus, Ehabdosoma). 

 The maxillipeds form a small bi- or tri-lobed under-lip. The paired 

 legs end in some cases in a powerful chela. The caudal styles are 

 sometimes lamellar and fin-like, sometimes styliform. Development 

 takes place by metamorphosis. They live principally in jelly-fish, 

 and swim very rapidly. 



Fam. Hyperidee. Head globular, almost entirely occupied by the eyes. The 

 two pairs of antennas have a multiarticulate shaft ; the flagellum longer in the 

 male. The mandible has a three-jointed palp. The fifth pair of feet is gener- 

 ally formed like the sixth and seventh, with claw-like terminal joint. Hyperia 

 (Lestrigonus Edw.) medusarum O. Fr. Mull. (7 galba Mont. = H. Latreilli 

 Ed\v.) with Lestrigonus exulans Kr. as male, North Seas. 



Fam. Phronimidae. Head large, with projecting rostrum and large divided 

 eye. The anterior antennae are short in the female, with only two or three 

 joints, in the male with long multiarticulate flageilum and a shaft closely 

 beset with olfactory hairs. The thoracic limbs have in some cases powerful 

 chelae. Phrosina nicceensis Edw., Phronima sedentaria Forsk. The female 

 lives with its offspring in Pyrosoma and Diphyidce, Mediterranean. 



Fam. Platyscelidae. Both pairs of antennae hidden beneath the head ; the 

 anterior are small ; in the male with much swollen bushy shaft, and short, 



