CALIFORNIA EUDRILID.K. 23 



below are Micrnsrnl<>.r duhlus of Rosa and EiidrUnK (hibina of Fletcher. I will first 

 refer to the lattei*. Fletcher's description is sufficiently minute to allow us with cer- 

 tainty to refer it to the genus, but the details are wanting to such an extent, that it is 

 difficult to understand its fui'ther I'elationship. There are three points in the descrip- 

 tion which are of special interest. 



1. Absence of spermathee;?. 



2. The beginning of the nephridia in v. 



3. The junction of the si)eruiduct and the [)rostate half-way between the 

 glandular part and the body-wall. 



As to the first of these the spermatheciie may be really wanting or it may have 

 a substitute similar to the one found in Ddtaida ek'yans as described below. At any 

 rate this character brings the species Eadrilus dabius close to Ddlania eleyans as well 

 as to Beddard's Mkroscolex Poidtoai. 



The beginning of the nephridia in somite v brings E. dulnuK close to Beddard's 

 species but separates it distinctly from Ddtania deijaua in which the nephridia com- 

 mence in ii, as will be shown below. 



The third cliaracter requires to be reaffirmed and described more in detail. 

 The joining of the spermduct and the prostate is always of the utmost importance and 

 interest and a mere general statement will not suffice for properly characterizing a 

 species, especially when the group is little known. 



Rosa at first considered E. dnbius to be identical with his Microscoie.v )nod- 

 estni^, but a later investigation of new material convinced him of the distinct char- 

 acter of the species and he then descril)es both as two different species of Microscolex. 

 It must therefore be considered certain that the deltoid arrangement of the ventral 

 setie does not occur in Microsco/e.c modeKtnif. In regard to the respective species of 

 E. dnbiux and M. didilus descrilxul by Rosa and Fletcher, I am not fully persuaded 

 that both actually belong to the same species, and I believe that nothing short of an 

 actual comparison of the specimens can decide if they do so. 



Beddard has at two different times described species of the genus Microscolex, 

 I)ut which differ from each other in several important points. Microscolex novcu-zdan- 

 diai resembles the old genus Rhododrilus in the independent opening of the spermduct. 

 Instead of referring the above species to Microscolex, and merge Rhododrilus in the 

 latter genus, I consider it more proper and convenient to retain Rhododrilus and re- 

 fer 31. novre-zdandun to it, as the independent opening of the spermduct appears to 

 me of sufficient importance to be considered a generic character. Another species, 

 Microscolex algeriensis, also described by Beddard, can, I believe, best be retained in 

 the genus Microscolex, as it evidently possesses the sette parallel throughout tlie 

 ventral side of the clitellum. 



Microscolex Poultoni however is probably a true Deltania and Beddard's excellent 

 description leaves no important characters in doubt. 



In his description of Microscolex Poultoni, Beddard refers especially to the 

 deltoid arrangement of the setic in the clitellial somites. He says: "From segment 



