EUPLECTINI 113 



ond segment of which is large and ovate; third to eighth moniliform and 

 slightly transverse; ninth and tenth segments progressively more transverse, 

 lenticular and symmetrical; eleventh segment ovate and as long as sixth to 

 tenth inclusive; (2) head wider than long, nearly as wide as pronotum; with 

 the vertex holding four foveae, one pair on a line through the posterior half of 

 the eyes, each nearer an eye than their mutual intrafoveal separation ; a second 

 pair of foveae placed near the subtruncate frontal margin, one on each side 

 at the base of the small first antennal segment; no vertexal sulci; (3) pronotum 

 with the biarcuate transverse subbasal sulcus terminating in a lateral fovea 

 each side, these foveae being visible from a dorsal point of view; (4) elytra 

 with obtuse humeri and each elytron having two large deep basal foveae. 



Ramelbida has but two genera with which it may be confused, Melba and 

 Trimiosella. From both of these it may be readily separated by the complete 

 absence of vertexal sulci (these sulci being obsolete in Trimiosella) , four well- 

 developed vertexal foveae (approached in this only by Melba (?) temporalis) , 

 and the visible pronotal foveae (which takes it from Melba). Many of the 

 species described in Melba may prove to belong in Ramelbida, but this may 

 not be ascertained until types are examined. At present there is but one: 



quadrijoveata (Raffray). 1904. St. Thomas, Virgin Islands. (Melba). 

 Genotype. 



MELBA (Casey, 1897) 



Casey (1897) 



Raffray (1898, 1904, 1908, 1908a, 1909, 1912, 1912a) 



Leng (1920) 



Bowman (1934) [Melba thoracioa (Brendel), p. 144, genotype) 



Brendel and Wickham (1890) {Trimium in part) 



Casey (1897) (Zolium) 



Reitter (1883) (Trimiopsis in part) 



Sharp (1887) [Trimiopsis in part) 



Like Jubus, Eurhexius, and Euplectus, this is a large and important genus ; 

 unlike Euplectus, it is wholly American, and appears to be one of the most 

 highly specialized in the euplectine tribe. There are about eleven described 

 species north of the Rio Grande river, distributed from Arizona eastward to 

 the Atlantic coast, and from Louisiana and Florida to New York and Illinois. 

 The genus does not appear to have any species spreading into Canada. South 

 of the Rio Grande, there are about eighteen species, eleven of which are endemic 

 in the Antilles, and the other seven species are recorded from Mexico, through 

 Guatemala, French Guiana, Brazil, and Argentina. Such a distribution appears 

 to indicate a neotropical origin for the genus, especially since related melba- 

 forms [Ramelbida, Trimiosella) are antillean also, and the Lesser Antilles are 

 the present center of taxonomic diversity in the genus. 



The habitus of Melba is fairly consistent (PI. XI, 7, 8). The species are 

 small (0.7 to 1.1 mm.), with a conspicuously large distal antennal segment, 



