TYRINI 317 



IX and X small; ninth with width and length equal, not much larger 

 than VIII; tenth with width and length equal, not much larger 



than ninth ; head very long, one-third longer than wide 



alleei new species 



Key to Species of Group XII 



Lateral pronotal margins tuberculate and sinuate above the lateral 

 pronotal foveae which incise the lateral contour; Mexico, .nodicollis 



Lateral pronotal margins simple; lateral pronotal foveae not incising 

 the lateral contour 2 



2. Distal palpomere of a peculiar form, being curved internally near 



apex which is acuminate; 3.5 mm.; Nicaragua pubiventris 



Distal palpomere not as above 3 



3. IX and X subglobular with all angles rounded; 2.5 mm.; Brazil.. 



appendiculatus 



IX and X not subglobular 4 



4. X subquadrate, either as long as wide or slightly longer than wide. ... 5 



X wider than long 6 



5. IX twice as large as VIII, X quadrate with length and width equal, 



twice the size of ninth but of nearly the same length ; XI very large, 

 oblique and ovoidal; 1.6 mm.; French Guiana sanguinipes 



IX twice as large as VIII, as wide as long, trapezoidal; X slightly 

 larger than ninth, trapezoidal, slightly longer than wide; XI of 

 normal size, as long as the preceding two united; 2.3 mm.; Mexico. . 

 electrae new species 



6. Intrahumeral impression strioid, clearly defined and one-half the 



elytral length; 2.3-2.5 mm.; Mexico, Guatemala and Costa Rica. . 



monachus 



Intrahumeral impression very short 7 



7. First two visible tergites of equal length; 2.33 mm.; Guatemala. . . . 



difficilis 



First tergite shorter than second (!) ; 2.33 mm.; Guatemala, .vicinus 

 This key does not include emeryi Wasmann, of Brazil. 



Key to Species of Groups XIII and XIV 



These two groups have been reorganized to accommodate new material 

 and the species incorporated into one key to avoid possible confusion in the 

 color of pubescence which, with one exception, varies from yellowish-brown 

 to brown. 



Pubescence a silvery gray; body length in excess of five millimeters; 



known only from colonies of anny ants ; Brazil ecitophilus 



Pubescence tawny to deep brown; body length less than three milli- 

 meters 2 



2. X longer than wide 3 



X with length and width equal, or much wider than long 6 



