Geometridae of the Argentine Be'puhlic. 299 
lower extremity ot cell ; very faint suggestions of median and post- 
median lines. Underside light brown-grey ; fore wing with the lines 
indicated at costa and the central shade across the wing ; hindwing 
with the markings rather stronger than above. 
La Paz, Mendoza, October 25, 1905 (W. M. Bayne), 
type in coll. L. B. Prout. 
Fovea wanting; SC^ connected with C, and anasto¬ 
mosing at a point with SC^'^. 
169, Xenoecista pallidata (Warren). 
Xenoecista 'pcdlidata, Warren, Nov. Zool., iv, 484' (1897). 
La Plata, in coll. Rothschild. 
Warren’s type was from the Amazons; he states {loc. cit.) 
that the La Plata specimen is rather larger and more 
darkly marked. Other localities are Colombia (coll. 
Rothschild), British and French Guiana and Paraguay 
(coll. Br. Mus.). . 
170. Thamnonoma tripartita (Prout), nov. sp. 
(Plate XLVIII, fig. 35.) 
(J. 24 mm. Forewing light clay-colour, dusted with fuscous grey, 
the dusting being the most dense in the median area and terminally ; 
proximal margin of central area weakly defined, from about one- 
third of costa, curved, then oblique basewards ; weak indications of 
a dark median shade near proximal margin of central area, nearly 
vertical, becoming more distinct at inner margin ; distal margin of 
central area weakly defined, but with a row of vein-dots indicating 
postmedian line, somewhat incurved distally to cell and bent distad 
at inner margin, otherwise parallel with termen, from costa at 
beyond two-thirds to inner margin at about two-thirds. Hindwing 
with basal and median areas rather strongly dusted with fuscous- 
grey, distal area somewhat lighter, more shaded with clay-colour ; 
a dark mark on inner margin indicates probably the point of origin 
of an obsolete antemedian. Underside more weakly marked, faint 
indications of the colour arrangement of the uppersurface. Head, 
body and legs more or less concolorous with wings. 
Aristides Villanueva, November 3, 1905 (W. M. Bayne) 
type in coll. L. B. Prout; La Paz, one ^ in coll. A. F. 
Bayne. 
In the coloration and in the weakness of the markings 
this species reminds a little of T. ochrifciscia, Warr., Nov, 
