1956] 
Darlington — Australian Carabidae 
9 
the following specific description. Genotype : Odontagonum 
nigrum n. sp., below. 
Odontagonum nigrum n. sp. 
Form of a broad, very convex Agonum; black, mod- 
erately shining, not iridescent, legs brownish black, anten- 
nae and mouth parts brown; upper surface impunctate 
except for fixed setigerous punctures; microsculpture light 
but normal, approximately isodiametric on head, trans- 
verse on pronotum, more transverse and oblique on elytral 
disk. Head rather elongate, only .57 and .59 width pro- 
thorax (in 8 2 measured) ; eyes much less prominent 
than in typical Agonum but not much reduced otherwise; 
genae rather short, oblique, slightly arcuate ; anterior 
supraocular setae absent, posterior ones present, about 
between posterior edges of eyes; antennae rather short 
(in tribe), normal except pubescent from middle of 3rd 
(not 4th) segments; mandibles, maxillae, and maxillary 
palpi all longer and more slender than usual in tribe; 
labial palpi shorter and stouter; mentum with triangular 
tooth; neck constriction weak; frontal sulci rather deep, 
linear, curved; clypeal suture distinct. Prothorax rather 
large, more narrowed in front than behind; width/length 
1.18 and 1.11 (in 8 2 measured); base/apex 1.3+ ; sides 
arcuate (not strongly) for most of length, less so or 
straight toward base ; basal angles rather narrowly 
rounded; anterior angles slightly produced, rather nar- 
rowly rounded; lateral margins wide posteriorly, nar- 
rowed anteriorly, rather strongly reflexed, each with seta 
about 1/3 from apex but none at base; disk convex; basal 
foveae moderate, not sharply defined, not punctate; middle 
line well impressed from extreme base nearly to apex; 
transverse impressions less defined; base not or vaguely 
margined; apical marginal line distinct at sides, vague 
at middle. Elytra 1.32 and 1.31 width prothorax (in 8 2 
measured), convex; basal margin strong and entire; 
humeri dentate; sides arcuate (only slightly so at middle), 
with moderate subapical sinuations; apices bluntly sub- 
acute but not produced ; lateral margins rather wide, 
forming slightly convex 10th intervals; sutural striae 
absent; other striae entire, deep, impunctate; intervals 
