8oo 



COMPENDIUM OF GENERIC DISTINCTIONS. 



Tribe. BIZONIA . Body cylindric, no platei on sides. 

 Antennae club-shaped, seven-jointed. Many segments, each 

 formed of two fused segments, and bearing two pairs of legs. 



Family. JULID^E. Feet fixed to immovable plates. 



Genus. JULUS. Head convex. Antennae long. Sides of 

 prothorax triangular. 



Genus. SPIROSTRKPTBS. Antennae short, with funnel- 

 shaped joints. Eyes transverse. Sides of prothorax lengthened 

 or widened. Asia. 



CLASS ANNELIDA. 



Elongated No jointed feet, often with bristles or 

 tubercles for progression Respiration by gills, sacs, 

 or skin. 



Order. SETIGERA. Body with bristles or bristle-bear- 

 ing rudiments of feet. 



Family. AMPHITRIT^. Head not distinct. Eyesnone. 

 Body mostly in a tube. 



Genus. SABELLA. Mouth transverse, across gills. Gills 

 two, feathery ; funnel comb-shaped, spiral, and large. Cylin- 

 drical stopper. Front tubercles with hooks and bristles. Tube 

 gelatinous, covered with sand. 



Genus. SERPULA. Gills two, combed, fan-shaped. Tube 

 not erect, calcareous, twisted. 



Genus. TEREBBLLA. Upper lip surrounded by long tenta- 

 cles. Tubercles with double row of hooks. Gills branching. 

 Tube composed of sand and shells. 



Family. NEREIDS. Body long, slender; head distinct, 

 with tentacles and eyes. Gills like lobes of feet. Tubercles 

 throughout all body. Proboscis large, often with two horny 

 jaws. No tube. 



Genus. PHYLLODOCE. Head small. Eyes two; tentacles 

 four or five, the last very minute. Jaws none ; proboscis thick 

 and tentacled. Two bristles at end of body. 



Genus. NEREIS. Eyes four ; tentacles four, short. Jaws 

 powerful ; proboscis thick and cylindrical. 



Family. EUNICES. Body long, many segments. Pro- 

 boscis with seven to nine horny jaws. 



Genus. EUNICE. Head distinct, tentacles five. Comb-like 

 gills in front of body. Jaws seven. 



Gamily. ARICIJE. Head scarcely distinct. Body small 

 at each end. Proboscis short ; jaws none. 



Genus. CIRRHATULUS. Body long, round, a few bristles 

 on back and belly ; cirrhi long. Gills like very long cirrhi in 

 front of body. 



Family. ARENICOLIDj<E. GUIs tufted In middle of 

 body. Double row of bristles along sides. Head not distinct ; 

 eyes and jaws wanting. 



Genus. ARENICOLA. Segments divided by folds, thick in 

 front, smaller behind; no bristles behind last pair of gills. 

 Mouth with retractile proboscis. 



Family. CHjETOPTERIDyE. Front and hinder tubercles 

 with a bundle of bristles, but without hooks. Those of middle 

 with a large membranous appendage. 



Genus. CH^TOPTBRUS. Long, enclosed in leathery tube. 



Family. APHRODITIDJE. Body oval. Head with 

 tentacles; eyes two or four. Flaps distinct, with spine and 

 bristles. 



Genus. APHRODITE. Head hidden under scales or bristles. 

 Eyes two; tentacles three. Jaws very small or wanting. 

 Body rather flattened. 



Family. LUMBRICIDJE. No gills. Body with bristles, 

 but no tubercles. 



Genus. LUMBRICUS. Nearly cylindric, narrow at both ends, 

 blunt behind. Mouth nearly at tip. Bristles not retractile. 

 Saddle composed of swollen rings in front of body. 



Order. SUCTORIA. Body without bristles, with a suck- 

 ing disc at one or both ends. No external gills. 



Genus. HIRUDO. Body oblong, rather flat. Jaws three, 

 with double row of crowded teeth. Eyes ten. 



Genus. H.SMOPIS. Double row of few teeth. Eyes ten. 



Genus. BRANCHIOBDBLLA. Body with large and few rings. 

 Eyes none. Jaws two, horny. 



Genus. ALBIONE. Body narrowed in front, rings numer- 

 ous. Mouth small, narrowed at bottom of front sucker. 

 Hinder sucker at end of body. 



Order. TURBELLARIA. Body cylindrical or flattened, 

 mostly not jointed, or wrinkled throughout, covered with cilia. 



Family. NEMERTIDjE. Body very long, very con- 

 tractile, indistinctly ringed. 



Genus. NBMERTES. Several eyes ; two pits at side of head, 

 surrounded by cilia. 



Sub-class. ENTOZOA. Parasitical. Mostly elongated. 

 No special organs of breathing. Found inside living animals. 



Order. STERELMINTHA. Intestine absent in some, 

 vascular in others. 



Family. CESTOIDE^. Body long, flattened, soft. No 

 mouth, head mostly with sucking discs. 



Genus. T*NIA. Body long, jointed. Head with four 

 sucking discs, mostly with beak surrounded with booklets. 



Genus. BOTHRIOCEPHALUS. Head swollen, with two or 

 four opposite furrows. 



Genus. ECHINOCOCCUS. Vesicles single or enclosed in cryst. 

 Many minute Entozoa in interior surface. 



Order. C^ELELM I NTH A. Intestine in a distinct cavity. 

 Tribe. NEMA TOIDEA.Ho&y round, elastic. 



Family. STRONGYLIDIDjE. Mouth at or nearly at end 

 of body, not surrounded with retractile hooks. Body round, 

 long, and elastic. 



Genus. STFONGYLUS. Body very long, sharp in front. 

 Mouth round or triangular. 



Genus. ASCARIS. Body sharp at both ends. Head three- 

 valved. 



Genus. TRICOCEPHALUS. Body thread-like in front, sud- 

 denly thickening behind. 



Genus. FILARIA. Body very long, thread-like, nearly 

 equal throughout. Mouth rounded. 



CLASS. ECH1NODERMATA. 



Radiate, skin more or less leathery, having variously 

 shaped chalky pieces imbedded. 



Sub-class. DITREMATA. Digestive canal distinct, with 

 two openings ; outline of body entire. 



Order. HOLATHUROIDEA. Shell none; no chalky 

 pieces. Body cylindrical, moving by alternate extension and 

 contraction. 



Family. THALASSEMAD^E. Proboscis with long, 

 fleshy appendage. No tentacles. Vent at end of body. 



Genus. THALASSBMA. Body cylindrical, rounded, and 

 smooth behind. Proboscis short. 



Family. PRIAPULID^E. Proboscis retractile. Tentacles 

 none. Vents at end of long tail. 



Genus. PRIAPULUS. Body blunt behind. Tail branched 

 and pointed. 



Family. SIPUNCULID^E. Proboscis retractile, tentacled 

 at tip. Vent at base. 



Genus. SYRINX. Proboscis shorter than body. Tentacles 

 fingered. 



Genus. SIPUNCULUS. Proboscis long as body. Tentacles 

 not fingered. 



Order. HOLOTHUROIDEA. Shell none. Skin with 

 chalky netted pieces ; a ring of same substance round gullet. 

 Locomotion mostly by suckers. 



Family. PSOLID^E. Suckers three rows on oblong disc; 

 two rows rudimentary. 



