ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 749 



OEDER II. BDELLOIDA. 



That swim and creep like a leech ; foot retractile, jointed, tele- 

 scopic, termination furcate. 



Fam. 3. Philodinadje. 



Trochal disk two transverse circular lobes ; wreath two marginal 

 curves on each lobe with mouth between ; or trochal disk of one lobe 

 ventrally furred with cilia ; trophi ramate. 



ORDER III. PLOIMA. 

 That only swim. 



* Hloricated. 



Fam. 4. HTDAXINADiE. 



Trochal disk transverse with ciliated prominences ; wreath double ; 

 trophi malleate ; brain small, not sac-liko ; foot furcate. 



Fam. 5. Synoh^tad^, 



Trochal disk roxmded ; wreath of interrupted curves, surrounding 

 the head ; trophi virgate ; foot absent, or minute. 



Fam. 6. Notommatad^. 



Trochal disk oblique ; wreath of interrupted cui'ves and clusters ; 

 trophi virgate or forcipate ; brain large, sac-like ; foot furcate. 



Fam. 7. TRIARTHRADiE, 



Trochal disk transverse ; wreath single, marginal ; trophi malleo- 

 ramate ; foot absent. 



Fam. 8. Asplanchnad^. 



Trochal disk rounded ; wreath single, marginal ; trophi incudate ; 

 intestine, anus, and foot absent. 



** Loricatcd. 

 Fam. 9. Braohionid^. 



Trochal disk transverse with ciliated j)rominenccs ; wreath single, 

 marginal ; trophi malleate ; lorica entire, simple ; foot transversely 

 wrinkled, wholly retractile, two-toed or absent. 



Fam, 10. Ptebodinadjb. 



Trochal disk two transverse circular lobes ; wreath on each 

 double, marginal ; trofthi raulleo-ramate ; foot transversely wrinkled, 

 wholly retractile, ending in a ciliated cup. 



