310 WHEELER. 



Eciton (Labidus) coecum Latreille. 



(Fig. 5e, Fig. Qc-h). 



This widely distributed, hypogaeic species, so common in southern 

 and central Texas and in many parts of Central and South America, 

 seems to be rare at Kartabo, where I found it only once, foraging under 

 some large logs in a damp spot near the laboratory. I saw it also in 

 the Botanical Garden at Georgetown. Although several varieties 

 of the male have been recognized {biloba Emery of Ecuador, jurinei 

 Shuckard of Brazil, scvUlci Westwood of Central and South America, 

 kulowi Forel of Mexico and hostilis Santschi of French Guiana), only 

 one variety, selysii Forel, has been recognized among worker speci- 

 mens. The validity of this form seems to me to be doubtful, as it was 

 based on rather small workers. All the soldiers and workers in my 

 collection, representing numerous localities from Texas to Paraguay 

 show very little variation, with the exception of a single soldier taken 

 by Mann at Para. This e\-idently represents a distinct variety which 

 may be called opacifrons var. nov. It differs from the soldier of the 

 typical form in ha\ing the head broader in front and less excised in 

 the middle of the posterior border, the tips of the mandibles are 

 coarser and much more decidedly incurved, with scarcely a trace of 

 the subapical tooth. The front, vertex and gula are opaque and 

 densely shagreened, instead of very shining as in the typical form and 

 the whole pronotum is opaque and sharply shagreened, instead of 

 being more or less smooth and shining on the sides. The hairs on the 

 body are shorter, more abundant, and of more even length, especially 

 on the dorsal surface of the head and thorax and on the legs. The 

 surface of the mandibles is very strongl}', arcuately rugose. The 

 legs, coxfe, petiole, postpetiole and gaster are distinctly yellowish, the 

 remainder of the body as dark red as in the typical coecum. Of course, 

 this form may be the unknown soldier of one of the varieties described 

 from male specimens. 



Eciton (Labidus) praedator F. Smith. 



Like coecum, this species has a very wide range, from Argentina to 

 tropical Mexico, but it is not known from the Sonoran Region or from 

 our Southern States. In habits it is somewhat intermediate between 

 the species of Eciton s. str. and E. coecum, making its forays above 

 ground when it is not convenient to keep under the dead leaves. It 



