ZOOLOGICAL RESULTS OF A TOUU IN THE FAU EAST. 
MYSIDACEA, TANAIDACEA AND ISOPODA. 
B\> W. M. Tattersall, D.Sc, Keeper of the Manchester Museum. 
(Pis. XV, XVI, XVII.) 
Dr. Annandale has kindly entrusted to me for examination the Crustacea belong- 
ing to the three' orders Mysidacea, Tanaidacea and Isopoda (marine or aquatic 
species only) which he procured during his tour in the Eastern parts of Asia. The 
collection contains sixteen species, seven Mysids, one Tanaid and eight Isopods and 
has proved of exceptional interest. I am much indebted to Dr. Annandale for the 
opportunity of examining it. 
The collections were made mainly in brackish or freshwater lakes and while the 
number of species collected is not large, some interesting results were obtained. 
In L. Biwa, Dr. Annandale found an Asellus which I am unable to distinguish 
from the cosmopolitan Asellus aquaticus of Eurppe and America. This discovery 
j&lls a gap in the known distribution of this species and links up its known occurrence 
over the greater part of Europe and Northern Asia with the records of the same 
species from America. It is a survival of the time when Japan was connected by 
land with the rest of the continent of Asia and with North America by the land 
bridge to Alaska. 
The most interesting specimens in the collection belong to a species of Caecido- 
thea found in a well in Otsu. This genus has hitherto only ' been found in North 
America. The Japanese species is of further interest in the fact that it possesses 
distinct eyes and may thus be regarded as a more primitive species than its North 
American congeners, which are all blind. Otherwise it is a true Caecidothea, afford- 
ing no characteristics to distinguish it generically. The record is a most interesting 
one from the point of view of geographical distribution. 
The remaining species from Japan in the collection were found as follows : — 
Marine species. 
Siriella watasei, Nak. 
Gastrosaccus vulgaris, Nak. • 
Anisomysis ijimai, Nak. 
Rhopalophthalmus egregius, Hansen. 
Brackish Water. 
•Neomysis awatschensis, Brandt. 
h. Kasumi-ga-ura. 
