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ZOOLOGY OF THE FAR EAST. 
The species in the above list show a great resemblance to one another in external 
form. They are all small, parallel-sided, linear species, the majority tubicolous in 
habit. The only marked exception is Cleantiella isopus, which has a quite different 
shape from the rest, and has, for this among other reasons, been made the type of a 
separate genus. 
Most of the species agree in having the fifth thoracic limbs shorter than the 
remainder, without a dactylus and with peculiar spines on the inner surface. 
C. isopus again forms an exception, to judge from Miers' figure, and Richardson says 
definitely that in C. heathii there is no perceptible difference in the length of 
the legs. 
Further, while the majority of the species have the flagellum of the second 
antennae composed of a single joint, C. heathii and C. sir assent have three and five 
joints in this flagellum. Moreover, in Zenohiana prismatica, the sexes differ in this 
respect according to Collinge, the male having 1-4 joints in the flagellum of the 
second antenna and the female only one with occasionally traces of a second. Issel 
has noted marked variation in this species in this respect. The species, C. str assent 
appears to be quite an anomalous form. In the segmentation of the metasome it 
approaches the genus Erichsonella , but the second antennae have a multi-articulate 
flagellum which is not characteristic of either Erichsonella or Cleantis according to 
the original generic definitions. 
Enough has been said to indicate the great confusion which exists in the 
classification of this small group of species on lines similar to that employed for 
other members of the family. 
More precise and detailed ■ information is required about the existing species, 
with special attention paid to the maxillipedes, segmentation of the metasome and 
antennal flagellum. We require a detailed study of the variation of the segments and 
sutures of the metasome and of the joints in the antennal flagellum in any one 
species or group of species in order to arrive at a conclusion as to their value for 
classificatory purposes. It is not possible to attempt a revision of the above group 
of species here, for I have no material at my command, but it has seemed to me 
well to call attention to the discrepancies and anomalies which at present exist, in 
the hope that some worker with the material at his command will take the question 
up and elucidate it. 
It will be seen, too, that it is almost impossible to be certain of the generic 
position of the new species described below. 
I do not feel it would be right to burden literature with a new generic name 
when investigation may remove the difficulties mentioned above, and I therefore 
refer the species for the moment to the genus Cleantis, Dana, emphasising that the 
species has five joints in the palp of the maxillipedes, four segments and one 
additional pair of sutures in the metasome, a two-jointed flagellum to the second 
antennae in both sexes, the fifth pair of thoracic limbs markedly shorter than the 
rest, and the uropoda without exopodite and with a plumose seta. 
