112 PROC. ENT. SOC. WASH., VOL. 31, NO. 6, JUNE, 1929 DESCRIPTION OF A BRUCHID IMMIGRANT INTO HAWAII BREEDING IN THE SEEDS OF CONVOLVULACEAE (COLEOP-TERA). Bv John Colburn Bridwell, Glencarlyn, Virginia. Under the manuscript name Megacerus pescaprae Falder-mann. Director of the Botanic Gardens at St. Petersburg, sent a Bruchid obtained from seeds of Ipomoea pescaprae from Brazil to Schoenherr for use in his work on the Curculionidae. Schoenherr considered it a Bruchus of his Stirps 2, Maniplus 2, and referred it to Fahraeus, who described it as Bruchus pes-caprae in Schoenherr 1839, Gen. Cure. 5:34, no. 48, citing Faldermann's manuscript name in synonymy. Under the International Code ot Zoological Nomenclature (see Opinion no. 4) this action validates the monobasic genus Megacerus with the genotype Bruchus pescaprae. This instance seems to be the oldest use of the genonym Megacerus. Jekel in 1855 (Insecta Saundersiana Col. Cure. 1:1) considered the group containing Bruchus pescaprae and B. coryphae Olivier as of generic rank and described it without using a generic name but placed the specimens in his collection under the name Pachybruchus which was published by Pic 1912 (Echange 28:109) as a subgenus. I fully agree with Jekel's opinion and with the suggestion made by Sharp 1885 (Biol. Centr.-Am. Col. 5:484) that the group seems entitled to generic recognition and it is here so treated as the genus Megacerus. The breeding habits of several species oi Megacerus are known and with one possible exception all are attached to the family Convolvulaceae, the larvae living in their seeds. Among these are our species discoideus (Say), impiger (Horn), coryphae (Oli-vier), and schaefferianiis new name [Bruchus croiatus Schaeffer 1909 not Bruchus crenatus (Fabricius) Thunberg 1791). Ma-terial of an undescribed species from Panama in the National Museum bears a label indicating the "silk cotton" as host plant. So far the genus is exclusively American, extending throughout the range of Convolvulaceae on the Continent and in the West Indies, and represented by many species in the American tropics. The species here described is the first of the genus to show migratory tendencies. The species of Megacerus may be separated into four groups of which the species here described falls into one having these characters: Mucro of hind tibia long and slender, as long as the tibial width at apex or longer, sculpture very strong, at least some of the elytral intervals bearing a row of punctures; body beneath, pygidium, and in part dorsum of pronotum and elytra bearing dense appressed pubescence concealing the sur-face sculpture and with certain characteristic denudate areas;
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