1917 Cockerell—New Social Bees 125 
Trigona tataira mediorufa (CkIl.). 
Trigona tataira salvatoris (CkIl.). 
T. mellicolor Pack. should apparently be kept distinct. The 
question whether to regard all these bees as species, or group them 
as races of an aggregate species, must be decided largely on grounds 
of convenience. The case is parallel to those frequently observed 
among ants. 
Trigona perangulata sp. nov. (clavipes subsp. ?) 
Worker: Length about 7 mm., slender; very close to 7. clavipes 
Fabr., differing thus: lateral face-marks coming up to level of top 
of clypeus; legs clear red, with trochanters yellow on outer side, 
anterior and middle femora yellowish above apically, middle 
basitarsi with most of posterior half black, hind tibtze broadly 
black posteriorly on apical half (this black area anteriorly with a 
large round lobe), hind basitarsi largely blackened; abdomen with 
four black bands, the first divided in middle by a cuneate paler 
area, the others angularly pointed in middle cephalad, and corre- 
spondingly notched caudad. 
Type: From Alhajuelo, Panama (Canal Zone), May 27, 1912 
(A. Buseck). U.S. Nat. Museum. Also from Pozo Azul, Costa 
Rica, June 15, 1902 (M. A. Carriker). 
Trigona pachysoma sp. nov. (postica subsp.?) 
Worker: Length about 6 mm., very broad and robust, with 
short abdomen. Very close to 7. postica Lat. (Prov. Sara, Dep. 
Sta. Cruz de la Sierra, Bolivia, 500 m., J. Steinbach), but with an 
obscure red spot on each side of face, wings strongly suffused with 
orange, nervures and stigma clear ferruginous, fifth abdominal 
segment without evident pale hair-patches. Compared with T. 
bipunctata Lep. (from F. Smith’s collection) it is more robust, 
with more highly colored wings; the facial spots in bipunctata are 
dull white. 
Type: From Porto Bello, Panama, April 20, 1912 (A. Busck). 
Also from Culebra, Canal Zone, 1910 (H. H. Rousseau). These 
insects have strong grooves on the mesothorax, which are lacking 
in the superficially similar 7. branneri Ckll. In T. branneri the 
ab. omen is dorsally polished and shining all over; in 7’. pachysoma 
dull, the bases of the segments shining. My T. postica is from the 
