Table 4. (Continued). 



Stomodeum 



Mesenteron 



Proctodeum 



Excretory system Nei-vous system 



Nemata 



"Esophagus" 

 triradiate, 

 stoma 2nd 

 invagination 



Cuboidal 2 cell- 

 rows to columnar 

 epithelium 

 bacillary layer 

 simple 



Cuticularly 

 lined rectal 

 glands often, 

 ventral anus 



Lateral canals 

 joined anteriorly; 

 ventral secondary 

 orifice; no 

 flame cells 



Partially fused vent, 

 nrv. indistinct series 

 of ganglia; nrv. ring 

 with large lateral 

 & ventral cephalic 

 ganglia 



Rotatoria 



Gastrotricha 



Triradiate Columnar or Cuticle lined Lateral canals Ventrolateral paired 



"mastax" cuboidal epith- dorsal anus joined anteri- nerves; with serial 



grossly elium, cilia. orly, open together ganglia dorsal and 



bilateral Simple. posteriorly into dorsolateral cephalic 



cloaca; flame cells ganglia 



Triradiate 

 "pharynx" 



Cuboidal epith- 

 elium 4-8 cell- 

 rows up ; no 

 lining. Simple. 



Cuticularly 

 lined; anal 

 glands some- 

 times; anus 

 dorsal or ventral 



Lateral canals 

 not joined, open 

 separately in 

 midregion on 

 ventral side; 

 flame cells 



Dorsal and lateral 

 cephalic ganglia and 

 lateral nerves 



Echinodera 



Non-radiate 



Columnar epith- 

 elium, no lining. 

 Simple 



Cuticularly 

 lined terminal 

 or ventral 



Short lateral 

 canals; not 

 joined ; open 

 separately, 

 laterally; 

 flame cells 



Dorsal and lateral 

 cephalic ganglia, 

 lateral and unpaired 

 ventral with series 

 of ganglia 



Acanthocephala 



None 



None 



Cuticularly 

 lined cloaca; 



Lateral canals 

 open together 

 posteriorly; 

 flame cells 



Nerve ringt with 

 associated ganglia; 

 lateral somatic 

 nerves. 



tQuestioned by 

 Van Cleave 



Nematomorpha 



Non-radiate. 

 ? Proboscis of 

 larva might be 

 triradiate 



Columnar epith- 

 elium. Simple 



Cuticularly lined 

 terminal 



None 



Nerve ring with 

 circum esophageal 

 ganglion mass and 

 ventral ganglion 

 mass with serial 

 nerve branching. 



Tardigrada 



Triradiate 

 "bulb" 



Cuboidal; Cuticularly lined ? Malpighian 



with bacillary with "Malpighian" tubule 



layer. Simple tubules. Ventral 



anus 



Nerve ring with 

 subdorsal and 

 subventral ganglia 

 and paired ventral 

 nerve with 4 pairs 

 of ganglia 



Arthropoda 



Non-radiate or 

 superficially 

 triradiate 

 pharynx 



columnar with 

 bacillary layer; 

 often highly differ- 

 entiated and with 

 2 muscle layers 



Chitin lining Malpighian tubules Circumesophageal 



partial, malpighian or head glands commissure and 



tubules paired ventral 



nerves with 

 metameric ganglia 



Annelida 



Non-radiate 

 pharynx 



columnar with 

 cilia or 

 bacillary 

 layer 



Cuticularly lined 



Open metameric 

 nephridia 



Circumpharyngeal 

 commissure w^ith 

 ganglia, and paired 

 with metameric 

 ganglia 



Turbellarea 



Nemertea 



Non-radiate 

 pharynx 



Columnar with 

 cilia or 

 bacillary 

 layer 



None or ? 

 atavistic 



Lateral canals 

 open separately 

 posterior ; 

 flame cells 



No ring; subdorsal 

 ganglia; lateral 

 and lateral cephalic 

 subdorsal and 

 subventral somatic 



Non-radiate 



Cecum; 

 lateral sacs 



Present 



Open or closed 



protonephridia; 



longitudinal 



vessels with 



sublateral 



orifices 



Circum-pharyngeal 

 commissure with 

 dorsal and ventral 

 ganglia and 

 lateral nerves 



199 



