DESCRIPTION OF MEXICAN ANTS. O 



Ectatomma ferruginous Norton (nov. sp.)- 



"Worker major. Length, 0.40 in. Color ferruginous ; 

 mandibles yellowish. Eyes round, widely separated. 

 Head longitudinally rugose, 

 basin of antennae very large, 

 touching the eyes and ex- 

 tending to top of head ; 

 three carinae between the 

 antennae, down the face ; be- 

 tween these, over the inser- 

 tion of antennae are two 

 shining tubercles. Mandi- 

 bles with fine striae. Head 

 transverse behind. Thorax 

 advanced, with a sort of tu- 

 bercle before, and a short 

 stout spine at each corner ; 

 scutum large and circular, with two tubercles on each 

 side, one on mesothorax, and one on the adjoining piece, 

 or parapsides ; two short separated spines on the declivity 

 of metathorax ; the pro and mesothorax with circular and 

 longitudinal, the remainder with transverse coarse striae. 

 Node subquadrate, prominent before, truncate above, 

 with circular striae ; first segment canaliculate through the 

 middle, with delicate diverging striae ; a deep incision be- 

 tween this and the next segment, which is covered with 

 very fine diverging striae ; apex of following segments 

 shining. Hinder tibiae and tarsi each one-third longer 

 than those preceding ; claws with a small inner tooth near 

 the middle. 



Male. Length, 0.40 in. Color piceous, varying to 

 black. Antennae set in a line with the bottom of eyes, 

 the summit of the basin in a line with top of eyes ; scape 

 short, about half as long as third article. Back of head 

 truncate, about one-third narrower than at eyes. Pro- 

 thorax distinct. Mesothorax trilobate as in Tenthredo, 

 rounded before, thorax with numerous longitudinal striae, 

 running (seen from behind) from the right down to the 

 left side. Node rounded, transversely striate, with a 

 short spine on each side before. Abdomen as in the 



