32 THE ROTIFERA. 



Division II. 



Foot transversely wrinkled, wholly retractile, furcate or ending in a ciliated cup ; 

 sometimes absent. 



Fam. 17. Pterodinad (PI. C. fig. 9). 



Lorica greatly depressed, entire, of two nearly equal plates, soldered together at the 

 edges ; corona and ciliary wreath those of the Philodinadce ; trophi malleo-ramate ] ; 

 foot ending in a ciliated cup. 



Fam. 18. Brachionida (PI. C. fig. 8). 



Lorica depressed, entire, dorsally arched, generally armed with anterior and posterior 

 spines ; corona transverse with styligerous prominences ; ciliary wreath single, marginal, 

 fringing the buccal orifice ; trophi malleate ' ; foot furcate, or absent. 



Order IV. SCIRTOPODA. 



That sivim with their ciliary wreath, and skip with Arthropodous limbs ; foot replaced 

 by two dorsal, stylate, unconnected appendages, ending in ciliated expansions. 



Fam. 19. Pedalionid (PI. C. fig. 11). 



Corona truncate ; ciliary wreath a marginal continuous curve, bent on itself at the 

 dorsal surface, so as to encircle the corofla twice, with the buccal orifice between its 

 upper and lower curves ; having also two gaps, the one dorsal between its points of 

 flexure, and the other a ventral gap in the upper curve opposite to the buccal orifice ; 

 trophi malleo-ramate. 1 



The further subdivision of each family into genera will be given with the description 

 of that family. 



1 For description of these technical terms, see pp. 28, 29. 



