248 UNIVERSITY OF COLORADO STUDIES 



tained at Burnt Knoll, Boulder County. Mr. M. C. Hall informs us that 

 Filaria atienuata Rudolphi and F. megacaiilha Leidy have been described from 

 Asio accipitrinus, an owl which also occurs in Boulder County. 



Order NEMATOMORPHA 



Family GORDIIDiE 

 These are the hair-like worms, popularly supposed to be transformed horse-hairs. 

 Montgomery has published {Proc. Acad. Nat. Soc, Phila., 1907) an account of 

 these animals, in which he records four species from Montana, two from Wyoming, 

 and one from New Mexico. The most abundant United States species is Para- 

 gordius varius (Leidy). 



Class ROTIFERA 



Microscopic aquatic animals, known as "Wheel-animalcules." We undoubtedly 

 have many genera and species, but only a few have been identified. 



Order BDELLOIDA 



Family PHILODINIDiE 



(88) Callidina Ehrenberg.* More than one species of this genus was found in the 

 pond on the University campus; they were submitted to Professor H. S. Jen- 

 nings. Another species was collected by Mr. E. Bethel on South Boulder Peak. 



Order PLOIMA 

 Suborder Loricata 



The five species enumerated below were all from the pond on the University 

 campus, and were determined by Professor H. S. Jennings. 



Family CATHYPNED^ 



(89) Monostyla Ehrenberg. M. bulba Gosse.* 



Family COLURIDiE 



(90) Colurus Ehrenberg. C. hicuspidatus Ehrenberg.* 



(91) Metopidia Ehrenberg. M. lepadella Ehrenberg* and M. salpina Ehrenberg.* 



Family ANURiEIDiE 



(92) Anuraea Ehrenberg. A. cochlearis Gosse.* 



Class CH^TOPODA Oerst. 



Worms with lateral bristles or chaetae for use in locomotion. 



Order OLIGOCHMTA 



This group includes the earthworms, of which we have various species, not yet 

 identified. 



