568 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 9 



It may, therefore, be expected to take up its residence at no remote date 

 in the hot-houses of the northern states. In all probability it has al- 

 ready established itself in numerous localities in tropical America, 

 from which orchids and other plants are being constantly imported. 



The worker T. striatidens (Fig. 39a and b) is very easily distinguished 

 from that of any of our American ants by the shape of the head and 

 thorax and the peculiar structure of the soft, dense, erect hairs covering 

 the body. It measures only 2.5 mm. and is orange-brown or dark 

 brown with the first gastric segment blackish and the mandibles, 

 antennae and legs brownish-yellow. The mandibles are striated, the 

 head, thorax, petiole and postpetiole subopaque, punctate and reticu- 

 late-rugose, the rugae on the upper surface of the head being longitudi- 

 nal. The gaster is smooth and shining. The head is subrectangular, 



Fig. 39. Triglyphothrix striatidens Emery, a worker in profile; b head from above. 



with the frontal carinas continued backward nearly to the posterior 

 corners and forming the inner borders of broad and moderately deep 

 scrobes into which the folded antennae fit above the eyes. The thorax 

 is short, without promesonotal and mesoepinotal sutures, with the 

 episternal angles projecting upward as spines and the epinotal spines 

 rather long, erect, pointed and very slightly recurved. The nodes 

 of the pedicel are somewhat flattened above, the petiole is anteriorly 

 pedunculate, its node a little longer than broad, the postpetiolar 

 node is rounded, about as broad as long, shorter than the petiolar 

 node. The body and legs are covered with soft, dense, erect 

 hairs, many of which are trifid from their insertions and therefore 

 suggested the generic name The female is a little larger than the 



