-L wo years ago, or 1878, while travelling among the snowy peaks of 

 California's Sierra Nevada, my attention was attracted to a smale lim- 

 icolide Oligochœte, which I at first sight easely recognized as new and 

 interesting. I was at the time not armed with any microscope or even 

 stronger lens, and could therefore not even preliminary study its vascular 

 system, and specimens which I attempted to preserve alive until my 

 arrival to the plains, died unfortunately already on the second day after 

 captivit3^ 



The worm was found in a small rapidly flowing spring, which for 

 9 months of the year must certainly remain icebound and whose waters 

 for the three remaining months never could have attained a temperature 

 of much over 40° Fahr. 



The few specimens which I preserved in alcohol proved upon 

 examination to belong to a worm, whose many new and remarkable 

 features placed it in an entirely isolated systematic position among the 

 Oligochaäta. To investigate the vascular system of the same I had no 

 other choice than to return the following year to the high Sierra-Crests 

 and, better provided with instruments, work out the circulatory part of 

 the anatomy on the spot. This successfully done the rest of the ana- 

 tomy was studied from dissections of alcoholic specimens. 



In the follo\ving I will first shortly characterize the Family and 

 genus and afterwards more minutely present the anatomical character- 

 istics and compare them with those of other nearly related families. 



Nova Acta Reg. Soc. Sc. Ups. Ser. III. 1 



