794 



COMPENDIUM OF GENERIC DISTINCTIONS. 



Genus. DOCLEA. Beak small ; claw-limbs large and power- 

 ful ; carapace with many long and stout spines. Hotter seas. 



Family. MAIAD^E. Legs moderately long, first pair 

 often larger than following ; base of outer antennae large. 



Genus. LISSA. Beak wide, notch shallow. Claw-legs 

 moderate. Carapace and limbs noduled. Warm and hot 

 seas. 



Genus. CHORINUS. Body large and rounded ; limbs rather 

 short ; beak long. Limbs, and sometimes body, noduled or 

 spined. West Indies. 



Genus. ARCTOPSIS. Carapace triangular, front with four 

 horns, the two central forming a beak. Eyes on short foot- 

 stalks. Abdomen seven joints. Many seas. 



Genus. HYAS. First joint at base of outer antennae flat- 

 tened and widened on outer side. Carapace wide and flat. 

 Many seas. 



Genus. MAIA. Movable stem of outer antennae within 

 comer of orbit. Carapace oval, beak stout. First pair of 

 legs scarcely larger than others. Abdomen with seven joints. 

 Most seas. 



Genus. MICIPPA. First joint of outer antenna: bent and 

 widened at upper end. Carapace truncated in front, and ter- 

 minated by a toothed bill. Philippines. 



Genus. PERICKRA. Lateral antennae inserted under muz- 

 zle. Seven segments in abdomen. West Indian seas. 



Genus. CRIOCARCINUS. Beak bifid, very long, and diverg- 

 ing. Eyes on long footstalks. Claw-limbs large: carapace 

 spmose. New Hebrides. 



Genus. ACANTHONYX. Beak short, deeply cleft ; claw- 

 limbs small, all the toes sharply hooked. Six segments in 

 abdomen of male. Mediterranean. 



Genus. HUKNIA. Lower edge of forehead sharp. Hinder 

 feet slightly keeled on front edge. Japan. 



Family. PARTHENOPID^E. First pair of legs much 

 larger than others, large, and stout. Carapace triangular. 



Genus. PARTHKNOPE. First pair of feet elbowed at claws. 

 Beak short. Abdomen with seven joints. Warm seas. 



Genus. LAMBRUS. Abdomen of male with five joints ; rest 

 like Parthenope. Warm and hot seas. 



Genus. CRYPTOPODIA. Carapace wide ; limbs capable of 

 concealment under shell. Japan. 



Genus. EURYNOMB. Beak with two triangular horns. Ab- 

 domen with seven joints. Eyes retractile. Carapace rough. 

 First joint of outer antenna: ending at inner corner of orbit. 

 Many seas. 



Tribe. CYCLOMETOPITA.Cznv*x wide, bow-like 

 in front, narrower behind. 



Family. CANCERID^. Carapace wider than long. 

 Legs not adapted for swimming ; hind-legs with pointed and 

 claw-like toes. 



Genus. CANCBR. Sides of carapace in front, many-lobed. 

 Inner antenna: folded longitudinally. Many seas. 



Genus ./ETHRA. Carapace much flattened; claw-feet in- 

 capable of being raised perpendicularly. Mauritius. 



Genus. XANTHO. Back rather flat. Abdomen with seven 

 joints in female, five in male. Inner antennae transversely 

 folded. 



Genus. PBRIMELA. Carapace about as long as broad. Ab- 

 domen as in last genus. Outer jaw-feet with fourth joint in- 

 serted into third of its inner edge. Many seas. 



Genus. PILUMNUS. Carapace convex and hairy. First 

 joint of outer antennae small ; four hinder pairs of legs hairy. 

 Many seas. 



Genus. MGLR (including ZOZYMUS). Carapace wide, toothed 

 in front. Claw-limbs strong ; legs broad and rather flattened. 

 Indian seas. 



Genus. _ CARPIUUS. Carapace round, smooth, sparely 

 toothed in front, wider than long. Claws very large and 

 powerful ; legs moderate. Mauritius. 



Genus. GALENE. Cephalothorax slightly bowed in mid- 

 dle ; right pincers largest in both sexes ; front legs squared. 

 Hot seas. 



Family. PORTUNID,*. Last pair of feet flattened, the 

 toe developed into a thin oval plate. 



Genus. CARCINUS. Carapace nearly as long as wide, front 

 projecting. Tarsi of hinder legs narrow. Many seas. 



Genus. PORTUNUS. Carapace broader than long. Abdo- 

 men of male triangular. Second to fourth pairs of legs with 

 long, narrow-grooved tarsus. Many seas. 



Genus. NBPTUNUS. Carapace much broader than long, 

 sharply toothed in front, developed into spines on each side. 

 Tarsi of hind-legs very wide. Warm seas. 



Genus. LUPA. Carapace wide and pointed at sides. 

 Claw-legs very long, claw slender. Hinder feet flat and 

 broad. West Indies. 



Genus. POLYBIUS. Carapace nearly circular. All legs 

 flattened, tarsi of fifth pair oval. Many seas. 



Genus. PODOPTHALMUS. Carapace flat, very wide. Claw- 

 feet large and lonj*. Footstalks of eyes enormously long and 

 movable, resting in groove when not raised. Claws short. 

 Mauritius and Philippines. 



Tribe. C A TOME TOPITA. Carapace, nearly square or 

 oval, front nearly straight. Eyes on long footstalks. 



Family. THELPHUSID/E. Carapace more or less oval. 

 Eye-footstalks short ; fourth joint of jaw-feet not inserted into 

 external angle of preceding. 



Genus. THELPHUSA. Carapace flat, smooth, broad, and 

 heart-shaped. External antennas very short, placed near foot- 

 stalks of eyes. Warm seas. / 



Family. GECARCINID/E. Carapace wide, thin, long, 

 or rounded. Eye-footstalks long ; fourth joint of jaw-feet in- 

 serted into external angle of preceding. 



Genus. GECARCINUS. Carapace heart-shaped, broad in 

 front, stout, blunt behind. Footstalks of eyes short, lying in 

 rounded furrows. South America. 



Family. PINNOTHERID^E. Carapace circular, front 

 mostly narrow. Eye-footstalks very short ; fourth joint of 

 jaw-feet springing from top or outer angle of third joint. 



Genus. PINNOTHERES. Inner antenna: concealed under 

 front of carapace. Body circular, rounded above. Abdomen 

 of male very small, of female large and swollen. Many seas. 



Family. MYCTIRID/E. Carapace rather triangular. 

 Body lamellated. Beak small, under which the eyes lie con- 

 cealed. Sternal plate wider than long. 



Genus. MYCTIRIS. Carapace delicate, convex, rather cir- 

 cular or narrower in front. Limbs long and slender. Claw- 

 feet long. Warm seas. 



Family. OCYPODID/E. Carapace rhomboidal, elevated 

 in front. Eye-footstalks long. Claws very unequal in size. 



Genus. OCYPODB. Eyes occupying greater part of foot- 

 stalks. A.bdomen of male very narrow, last joint triangular; 

 that of female is oval. West Indies. 



Genus. GELASIMUS. Last segment of abdomen in male 

 semicircular, in female nearly round. Hct seas. 



Family. GONC-PLACID.*. Carapace rhomboidal, front 

 margin and sides forming continuous lines. Front very wide. 

 Outer antennae lodged below front and horizontal. Eye-foot- 

 stalks very long. 



Genus. GONOPLAX. Carapace very wide in front. Eye- 

 footstalks inserted near middle of front, very long, slender, 

 reaching to front angles. Claws in males long and cylindrical. 

 Abdomen of both sexes with seven joints. Temperate seas. 



Family. GRAPSIDJE. Body compressed. Eye-foot- 

 stalks short, thick, the eye occupying half their length. Front 

 limbs short. 



Genus. GRAPSUS. Carapace not narrower in front than 

 behind. Middle antennae lodged under front. Hot seas. 



Genus. PLANES. Carapace longer than wide, front pro- 

 jecting. Tarsi thick and spined. Temperate and warm seas. 



Tribe. OXYSTOMA TA . Outer jaw-feet when closed 

 forming a triangular point. Outer antenna: very small. 



Family. CALAPPIDj'E. Last four pairs of feet concealed 

 under carapace, first pair folded and coinciding with the general 

 outline. 



Genus. CALAPPA. Antennae like those of Cancer. Claws 

 very large, compressed, and notched at upper edge, folded so 

 as to cover mouth. Warm and hot seas. 



Genus. THEALIA. Carapace rounded, with projecting 

 spikes at sides and back. Legs rather long. China. 



Genus. CAMARA. Carapace round, smooth, and wida, 

 simple at edges. Claw-feet very flat. Mauritius. 



Family. LEUCOSIID^E. Outer jaw-feet when closed 



