92 
Psyche 
[June 
A NEW SPECIES OF WATER MITE FROM THERMAL 
SPRINGS 
By Ruth Marshall, 
Rockford College, Rockford, Illinois. 
During the summer of 1927, Professor Charles T. Brues, of 
the Bussey Institution for Research in Applied Biology, found 
several water mites in collections made in thermal springs of 
Nevada in the course of his investigations upon the life in such 
habitats. He kindly sent these specimens to the writer for 
further investigation. 
A search in the literature of the Hydracarina reveals very 
few records of their occurrence in thermal waters. Dr. Karl 
Yiets, of Bremen, who has studied the group extensively, con- 
firms this statement in a private communication to the author. 
The earliest account appears to be that of Plateau (2) who 
records the finding of Hydrachna cruenia in springs of a tem- 
perature of 46 °C., at Luxeuil, France, in the course of experi- 
ments on the determination of the thermal death point of several 
fresh water arthropods. This record is quoted by Brues (1) in 
recent papers on life in thermal waters. The identity of this 
species seems to be in some doubt, but it is probably a widely 
distributed European form. 
Two other records have appeared during the past year. 
Uchida (4) has described a new species, Eylais thermalis from a 
single specimen found in a spring of temperature 42 °C., near 
Taihoku, in the island of Formosa. Dr. Iwan Sokolow (3), ex- 
amining material collected near Lake Baikal, Siberia, in springs 
of temperature 45 °C., found three individuals which he has des- 
cribed very fully and named Thermacarus thermobius, a new 
genus and new species. He has also erected for them a new 
family, Thermacaridce. The American material is a new species 
belonging to this genus, to which the name Thermacarus neva- 
densis has been given. 
