RESEARCHES IN AMERICAN OLIGOCH^TA, 



WITH ESPECIAL REFERENCE TO THOSE 



OF THE PACIFIC COAST AND 



ADJACENT ISLANDS. 



BY GUSTAV EISEN, PH. D. 



CONTENTS. 

 Plates V-XIV. 



Page. 

 GEOSCOLECID^. 



PONTOSCOLEX 87 



Caudal Zone 93 



Auditory Cells 96 



Protective Structures loi 



Intra-typhlosolar Canals 105 



OCNERODRILINiE. 



OCNERODRILUS HO 



(OCNERODRILUS) HO 



Structure of Spertn-sacs in Ocnerodrilus 113 



(Enicmodrilus) HO 



(IlYOGENIA) 112 



(LeIODRILUS ) 112 



(NeMATOGENIA) • • • 112 



Nematocytes tn Nematogenia 131 



(PyGM^ODRILUS ) 112 



(HapLODRILUS) 112 



Kerria 135 



EUDRILIN^. 



EUDRILUS 135 



Epidermal Sense-cells 143 



ACANTHODRILIN^. 



NOTIODRILUS 147 



MICROSCOLECIN^. 



MiCROSCOLEX 151 



Yagansia 152 



Rhododrilus 153 



[85] December 14, 1899. 



