158 PROCEEDINGS OF THE NATIONAL MUSEUM vol.84 



Descriptions of the new species of Megascolides in this paper are 

 based on material received from different parts of Oregon. F. M. 

 McElfresh, of Salem, Oreg., in the autumn of 1899 sent a single 

 specimen, collected in the Cascade Range, that belongs to an unde- 

 scribed species of this genus. No data concerning the exact location 

 and date of collection are available. In January 1903, Mr. McEl- 

 fresh sent a specimen that had been collected at or near Salem, and 

 it was found to belong to another species of Megascolides. These 

 two specimens and tAvo others belonging to a new subspecies of 

 PluteUus were carefully studied as the basis for a thesis in partial 

 fulfillment of the requirements for the degree of master of arts in 

 zoology in the Graduate School of the University of Illinois in 1917 

 by Lola E. Swift (Faust) under the supervision of the writer. The 

 results of this study have not had formal publication and have been 

 utilized in part herein. In February and March 1931, F. E. Gar- 

 lough, director of the Control Methods Research Laboratory of the 

 United States Biological Survey at Denver, Colo., sent material that 

 included collections made in Oregon at Netarts, near the Pacific 

 coast, and at Multnomah in the northern interior part of the State. 

 These collections include specimens of new species of Megascolides 

 and PluteUus. 



The material from these various sources has supplied data for the 

 description of the following new species and subspecies : Megascolide.^ 

 cascadensis^ M. macelfreshi.^ M. michaelscni, M. eiseni, PluteUus gar- 

 loughi^ P. oregonensis., P. o. swiftae. 



Two of the new species of Megascolides are based on but a single 

 specimen of each, and these were collected at a time when the repro- 

 ductive organs were not fully developed. When these specimens 

 were prepared for examination, lack of experience in studying such 

 animals resulted in a lack of the best mode of their preparation for 

 such study and hence in less adequate data than would be desirable. 

 The differences between these individuals and those of other kinds 

 studied are sufficiently great to convince the writer that they must 

 belong to distinct species, and they have been so treated, in spite of 

 the desirability of having a larger number of specimens and more 

 adequate data. It is hoped that more extensive collections from 

 various parts of Oregon and adjacent States may be made and stud- 

 ied, for still other new species of Megascolecidae probably may be 

 found in that region. 



TERMINOLOGY 



Before presenting details of anatomy in the descriptions, it seems 

 desirable to refer briefly to the terminology used. There is much 

 diversity in the terms used by different writers in describing the 



