JAMES A. G. REHN 327 



linguiform, tectate, carinate dorsad. Cephalic femora with distal 

 five-eighths very slender; discoidal spines three in number: 

 cephalic tibiae abbreviate, not a third as long as the femora, in 

 addition to the claw with an internal, an external and two distal 

 spines, proximal portion of the ventral margin with a series of 

 several small denticulations. Median and caudal limbs elongate; 

 femora faintly swollen in the pregenicular region; genicular lobes 

 produced, rounded acuminate; caudal metatarsi forming dis- 

 tinctly more than half of the entire tarsal length. 

 Genotype. — P. tristani new species. 



Pogonogaster tristani new species (PI. XVIII, figs. .5 and 6; pi. XX, fig. 1.) 



Type. — 9; La Palma, Costa Rica. Elevation, 1600 meters. 

 May, 1906. (J. Fidel Tristan.) [Academy of Natural Sciences 

 of Philadelphia, Type no. 5353.] 



Size medium: form moderately elongate, abdomen fusiform: surface un- 

 polished. 



Head in general form transverse, subtrigonal: occiput when seen from the 

 cephalic aspect transverse truncate, with very low and rounded juxta-ocular 

 swellings: front dorsad of the ocelli with a fine but decided, transverse arcuate 

 carination: facial shield strongly transverse, low, the width at least three times 

 the greatest depth, dorsal margin arcuate, dorso-lateral angles obtuse: clypeus 

 produced in a conical tubercle: eyes prominent, almost semicircular in outline 

 when seen from the front, when seen from the dorsum the eyes are subglobose, 

 when seen in lateral view the eyes are ovate in basal outline: antennae imper- 

 fect, proximal joint small. 



Pronotum when seen from the dorsum has the general form elongate cruci- 

 form, the greatest width across the supra-coxal expansion subequal to the 

 length of the collar and about two-fifths of the entire pronotal length, when 

 seen from the side the pronotum is bisigmoid, the collar and the caudal extrem- 

 ity ascending, the portion between gently arcuate dorsad: collar with the mar- 

 gin well-rounded cephalad, faintlj' narrowing at the middle of the collar, thence 

 regularly expanding to the acute apices of the supra-coxal expansions, the 

 latter subfoliaceous and arcuate dorsad; shaft regularly narrowing from the 

 maxinmm width of the supra-coxal expansions to about the cephahc two-fifths 

 of the shaft, thence regularly but very sUghtly expanding to the caudal ex- 

 tremitj'^, the caudal margin arcuato-truncate: surface of the pronotum 

 with, on the shaft a decided median conical tubercle and a smaller but similar 

 one cephalad of the median protuberance, on the shaft at the caudal margin 

 is situated a pair of closely placed, j)rominent, rounded tubercles; collar with a 

 faint median carina, shaft with a distinct and continuous meihan carina, which 

 at the cephalic two-fifths and at the caudal four-fifths develops small, erect, 

 rounded lobes, the cephalic one the larger; serrulations of the margins more 

 regular and numerous on the collar and caudad on the shaft, sparser cephalad 



TRANS. .\M. ENT. SOC, XLIV. 



