170 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 95 
Diagnosis.—This species is undoubtedly close to R. teres Clay, from 
Nothura maculosa peruviana and Nothoprocta p. pericardia, and may 
possibly prove to be conspecific with it. 
It differs from teres in the following particulars: The length of 
body is less in both sexes, while the head in the male is slightly longer 
but much narrower, and in the female both slightly shorter and much 
narrower; the prothorax is noticeably shorter and narrower in both 
sexes, while the mesothorax is much narrower and the abdomen 
shorter. 
It is impossible to compare the measurements of the genitalia, since 
those for teres are not given. In teres the abdominal tergites are 
continuous in segments I, VI, and VII and separated in II to V, but 
in subteres they are continuous in al] abdominal segments, but not 
strongly chitinized or deeply pigmented, and are so closely fused with 
the pleurites that the suture is completely lost, while the pigmenta- 
tion of the latter sclerites is but little deeper than in the tergites. The 
markings on the pleurites may be seen clearly in the accompanying 
figure. The chaetotaxy of the abdomen is quite different. In teres 
there are two hairs at posterolateral angle of segment VI, instead of 
one; there is a longish hair at the inner posterior corner of the pleu- 
rites of segments I to V, with two more in the median portion of the 
posterior margin of pleurite IV; there are two hairs on the median 
portion of the posterior margin of tergal plates I to V, while on 
segment VII there are three long and one short: hairs on each side 
of posterior margin (the two long ones submarginal). 
MEASUREMENTS OF RHYNCOTHURA 
subteres 
heterura 
(male) 
Structure Male Female 
Length | Width | Length | Width } Length | Width 
BS ore hy aeia ie a ley inate NUL ee AN A Ma DE GS iit Dataset 1h nS UG ak 2. 04 
Ja Koy OVS) Sheep a Ses rg a a Urges Us NUNC Ae Ac fa ASH Ba rg OFS 66)s | Waar O23 Sip yl Ria ee ee 0. 43 
Head temples esi ee iin WENN 0. 41 0. 445 0. 48 0. 586 0.52 0. 56 
OCCLP UGA AACA Sr EAN UDI ana OAD RSE ALN RAD ign Reena 0. 52 
Prothoraxeysanewy ea Wy aye ae avin 0.15 0. 305 0.12 0. 305 0.14 0,347 
Wiesot hora xct teen ili cet ss URGE ea! 0.15 0. 456 0.175 0. 51 0. 24 0. 59 
Mie tat hora xe uieise orn Gell a ann ONE 0.17 0. 37 0.16 0. 41 0. 195 0. 48 
SAD LOMNEN saan yk Wain SUMS Negilly Decider ally. 444 0. 96 0: 58 0.90 0. 69 1, 24 0. 84 
FATAC ONAN AE ON NCL UUS GNRUI LE RISE Naa SRM Rae ga) 0. 26 0. 082 0. 25 0. 083 0. 217 0. 045 
TPL QIN OLS Hee MB EA I LONUSLL VENA IDS UCN Noe NRE VBE Nas 0. 065 0. 064 0.10 O08) nile tae 
HN GOMET Al Pl Aves eee URN aa 0. 073 0. 023 0. 098 0.043 |.....-.-2- 
As in teres, the female of subteres is considerably larger than the 
male in all its dimensions except the filiform antenna, which is 
shorter. The head is also differently shaped from the male, the post- 
antennal margins being straight in the male and concave in the fe- 
