58 Fresh-water Biology 



{Continued from page 56) 



6 — Colonial, frequently in spherical clusters. Clusters attached, (Lacinularia), Mega- 

 lotrocha, Sinantherina. Free swimming colonies or cluster (fig. 9) Conochilus. 



— Not attached, inhabiting a tube (fig. 9) . . . .•■•.•. Conochilus 



— Attached, separated, or in branching colonies of one to 30 individuals 7 



7 — Corona of 3 or 4 lobes (fig. 8) (Floscularia Cuv.) _. . ..Melicerta 



— Corona with not more than two lobes. Dorsal antenna present, Limnias: dorsal 

 antenna not evident (Ptygura) Oeclstes 



8 — Body with skipping appendages; no foot. (Fig. 41) Pedalia 



— Foot usually present 9 



9 — Animal with flexible cuticle (Illoricata) 10 



— Animal with stifi^ armor (Loricata) 19 



10 — Foot narrow stilette form, corona heart shaped (fig. 12) Microcodon: foot shorter, 



corona circular MIcrocodides 



— Foot absent, or foot with two toes 11 



11 — Intestine ends blindly, no anus; body sac like 12 



— Anus present 13 



12 — Body large, cuticle delicate; stomach without blind evaginations. Foot present' 



Asplanchnopus ; foot absent (fig. 13) Asplanchna 



— Body very small, cuticle firm; stomach with blind sacs Ascomorpha 



13 — Foot lacking; body with skipping appendages. With 12 blade-like appendages (fig. 18)' 

 Polyarthra; with two or three appendages (fig. 16) Triarthra, Pedetes, Filinia. 

 — Foot present, body without skipping appendages 14 



14 — Corona large, nearly transverse, with prominences bearing styles 15 



— Corona without prominences bearing styles 16 



15 — Form broad, corona transverse, flat or convex with four long styles and two ciliated 

 auricles (fig. 14, 15) _ Synchaeta 



— Two eyes. Slender foot, stomach 6-lobed (Enteroplea) Triphylus; corona extended 

 into a large fringed proboscis (Rhinoglena) Rhinops 



— One eye or none. Eye apparently wanting, body long conical (fig. 17), (Epiphanes) 

 Hydatina; one eye, body quadrate or sac-like (Epiphanes) Notops; one eye, body 

 long conical, humped Cyrtonia 



16 — With auricles, sometimes retracted 17 



— Without auricles 18 



17 — With three eyes Eosphora 



— With one eye. Body with many transverse folds, Taphrocampa ; body without such 

 folds (inclusive Copeus) Notommata 



18 — One eye. Eye cervical, Proales; eye near front Furcularia 



— Two eyes. Eyes cervical (Dicranophorus) Distemma; eyes frontal (fig. 19) (Cephalo- 

 della) Diglena 



19 — Foot present ^0 



— Foot lacking. Armor oval compressed (fig. 40) (Chromogaster) Anapus; dorsum of 

 armor with longitudinal striations (fig. ZZ, 34), Notholca; dorsum of armor marked 

 with polygonal areas, anterior margin spined (fig. 35, 36) (Keratella) Anuraea; 

 similar but anterior margin not spined Anuraeopsis 



20 — Foot transversely ringed or wrinkled; very retractile 21 



— Foot not wrinkled though often jointed 22 



21 — Foot ending in a cihated cup, armor dorso-ventrally flattened (fig. 28, 29) , . .Pterodina 



— Foot ending in one or two toes. Armor arched dorsally, flat or slightly convex ventrally 



(fig. 30) Brachionus; armor irregularly oblong, marked with grooves (fig. 37) 



Ploesoma; armor compressed laterally, without distinct grooves (fig. 38). Gastropus 



