454 
ZOOLOGY OF THE FAR EAST. 
scribed by reference to the figures given herewith and by pointing out the differences 
between the two forms. 
T. malayensis differs from T. japonica in the following points : — 
(1) absence of serrulations on the hind margin of the third segment of the 
pleon (pi. XXI, fig. i6) ; 
(2) there are only three joints in the flagellum of the first antenna ; 
(3) the second thoracic limb of the female (pi. XXI, fig. 11) has no trace of a 
palm and is therefore strictly simple in type ; 
(4) the presence of a distinct lobe on the merus of the second thoracic limbs 
of the male and the more pronounced lobe on the carpus of the same 
limb (pi. XXI, fig. 13) ; 
(5) the shorter and broader hand of the third thoracic limb of the male ; 
(6) the hind margin of the second joint of the last thoracic limb (pi. XXI, 
fig. 15) is minutely serrated throughout, the serrations much more 
numerous than in T . japonica. 
Small differences in the proportions and armature of the limbs, telson and uro- 
pods can be detected by a comparison of the figures given for the two species [pi. 
XXI, figs. II-20j. 
Length of the largest male, 7 mm., of the largest female, 9 mm. [This is the most 
completely terrestrial Amphipod with which I am acquainted. It is found in damp 
places at considerable distances from water. .4 ] 
Remarks. — Stebbing ( 1906 ) refers nineteen accepted and two doubtful species 
to the genus Talorchestia. Since that date I have described one new species, T. kem- 
pii, and referred Orchestia parvispinosa, Weber, to this genus and Barnard ( 1916 ) 
has described three new species from South Africa, T. quadrispinosa, T. ancheidos and 
T. australis and transferred Orchestia capensis to the genus Talorchestia. The latter, 
therefore, now includes twenty-five accepted and two doubtful species. 
By the use of the key to the species provided by Stebbing we find a group of 
very closely allied forms at the end of the key grouped under the headings 17 and 
18. These species are T. brito, Stebb., T. novaehollandiae, Stebb., T. martensii, 
Weber, T. kempii, W.M.T., T. parvispinosa, Weber, T. ancheidos, Barnard, and 
T. australis, Barnard, to which must now be added the two species described 
above. 
These nine species are very closeh'' related to one another but may be separated, 
partially at any rate, in the following manner : — ■ 
I. Side-plates 2-4 without a well-marked lobe or tooth on the hinder 
posterior border . . . . . . . . T. ancheidos, Barn. 
II. Side-plates 2-4 with a well-marked lobe or tooth on the hinder 
posterior boder. 
(a) Second thoracic limb ( first gnathopod ) of the male without 
a. meral lobe. 
(i) Hind margin of the third pleon segment with a few small 
serrations . . . . . . . . T. japonica, W.M.T. 
