MYRMEDONIA.—ORPHNEBIUS. 209 
seventh segment obscurely crenulate. Wings ample. Legs yellow, hind tarsi elongate, 
first and second joints both long, the former the longer. 
The unique individual described is no doubt a male; and it is possible that the 
peculiar punctuation of the sixth segment may be a sexual mark. 
20. Myrmedonia mimula. (Tab. V. fig. 21.) 
Nitidula, picea, elytris dilutioribus, antennarum basi et articulo ultimo pedibusque sordide testaceis; pro- 
thorace transversim subquadrato, elytris angustiore, fere impunctato; elytris sparsim punctatis ; abdomine 
levigato. 
Long. 34 millim. 
Hab. Panama, Volcan de Chiriqui 2000 to 3000 feet (Champion). 
Antenne rather short, and at the base rather slender, but much thickened outwardly, 
third joint almost as long as second, eighth to tenth each transverse, the tenth more 
conspicuously so; terminal joint large, equal to the two preceding together. Head 
broad and short, shining, very obscurely punctulate, eyes rather small. Thorax a good 
deal narrower than the elytra, considerably broader than long, nearly straight at the 
sides, the surface shining and almost impunctate. LElytra slightly longer than the 
thorax, slightly narrowed towards the shoulders, very sparingly punctate, the punctures 
rather indistinct, but conspicuously setigerous. Hind body polished and shining, the 
lateral margins much elevated. 
_ The unique individual described is a male. It has on the middle of the sixth dorsal 
plate just before the hind margin two slight, somewhat elongate, tuberculiform eleva- 
tions, and a similar but smaller and therefore still more indistinct elevation on each 
side; the seventh plate has on each side behind a slightly raised side margin, and the 
hind margin is obscurely crenulate, while in front of this the surface bears some 
granular elevations. 
Although this insect resembles Orphnebius in appearance, it is allied to Myrmedonia 
teres, and, like it and WM. longipes, has the head borne on a rather broad but unmista- 
kable neck; the basal joint of the hind tarsus is elongate, and about equal in length 
to the two following together. 
ORPHNEBIUS. 
Orphnebius, Motgchoulsky, Bull. Mose. 1858, pt. ii. p. 263, t. 1. fig. 8. 
Motschoulsky’s genus Orphnebius was characterized in only a few words, as follows :— 
“Form of the Myrmedonie with narrow thorax and enlarged abdomen, such as 
M. canaliculata and M. collaris, but differing by the structure of the tarsi, the longest 
(“ plus long”) joint of which is the second and not the first, and that of the antenne, 
which, being very elongate, offer as their shortest joint the terminal one. Wings short, 
not fit for flight.” The unique species for which Motschoulsky established the genus 
BIOL. CENTR.-AMER., Coleopt., Vol. I. Pt. 2, July 1883. 2 HE 
