738 STAPHYLINIDA. 
margin near the apex more or less swollen, and occasionally this is carried to such an 
extent as to cause this horn to have a broad emarginate extremity. 
7. Leptochirus serriger. 
Depressus, niger; abdominis segmentis basalibus ad basin anguste rugulosis; mandibulis parum elongatis, 
absque dentibus molaribus, sinistra dentibus quatuor tenacibus et basin proprius dente quinto minore ; 
dextra dentibus tribus tenacibus, et basin proprius dente quarto minuto. 
Long. 12-13 millim. 
Hab. Mexico (Truqui), Cordova (Sallé), Jalapa ([ohr). 
I establish this species upon four examples which I am unable to comprehend under 
either Z. edax or L. molossus. LL. serriger scarcely attains the size of the smallest 
examples of those species; the left mandible is armed internally with five teeth, 
which gradually decrease in size from the apical to the basal one, this latter being 
merely a tubercle ; the apical tooth on the right mandible is large, and is followed by 
two equal rather approximate teeth, between which and the base the mandible itself 
is much narrowed and bears a small tubercle and still nearer the base a yet more 
rudimentary prominence ; and the front of the vertex is much produced in the middle. 
8. Leptochirus gracilis. 
Depressus, niger; pectore, elytris pedibusque castaneo-rufis; abdomine parum sculpturato; mandibula sinistra 
dente erecto subparallelo, apicem versus haud acuminato, apice ipso emarginato. 
Long. 11-12 millim. 
Hab. Panama, Volcan de Chiriqui 2500 to 4000 feet (Champion). 
This insect is readily distinguished by the colour of the wing-cases and the 
peculiar form of the erect tooth on the left mandible; the armature of the inner 
margin of the mandibles is very similar to that of some of the extremely small 
varieties of L. edax. The characters are quite constant in the five examples before 
me. 
§ 2. Mandibule dente superiore et dente, vel tuberculo, supero-basali munite. 
9. Leptochirus punctiger. 
Nigerrimus, sat depressus ; vertice anterius in medio punctis duobus majoribus notato ; mandibulis brevibus, 
dente supero-basali parvo ; antennis sat elongatis. 
Long. 15 millim. 
Hab. Mexico, Oaxaca, Orizaba (Sallé), Jalapa (Hoge). 
This is apparently the least rare of the species of this group. JL. punctiger is similar 
to L. meaxicanus, but has numerous points of distinction: the supero-basal tooth of 
the mandibles is only an acute tubercle; the superior tooth is large and strongly 
directed inwards, its inner margin, however, being only feebly sinuate; the mandibles 
themselves are rather short, and the basal or molar tooth on each is large and consists 
