416 Philippine Journal of Science »» 



vein deeply sinuous, the discoidal cell being thus much 



narrowed on the basal half Monacrostichus Bezzi. 



g\ Basal joints of antennae united in the shape of a common 

 petiole - Callantra Walk. 8 



The first three genera, as far as known, are not represented 

 in the Philippines. Dacus and Tridacus are not Oriental; the 

 two species of true Dacus found in India (loyigistylus Wied. and 

 brevistylus Bezzi) are evidently of African origin; Dacus asiat- 

 icus Silvestri • is only a variety of the Mediterranean D. oleae 

 Gmelin; but the presence of true Oriental forms lacking pre- 

 scutellar bristles is demonstrated by the two Philippine species 

 described below; and moreover by the recently described Tetra- 

 dacus tsuneonis Miyake, 1 " from Japan, as well as by the Austra- 

 lian Dacus cucumis French, which lacks also the anterior supra- 

 alar bristle. 



The Philippine species without prescutellar bristles (atrichus 

 and ablepharus) , are evidently more closely allied to Chaetodacus 

 than to Tridacus, as shown by their sexual wing dimorphism, 

 and by their close affinity with cilifer Hendel, which has well- 

 developed scutellar bristles. They have no close affinity with the 

 African species of Dacus sensu stricto, like annulatus, mochii, 

 blepharog aster, erythraeus, etc., which usually have a noncil- 

 iated third abdominal segment in the male and are likewise 

 prevalently black and of a rather small size, but all have no 

 anterior supra-alar bristle, partly fixed abdominal segments, and 

 no brown anal stripe on the wings. A possibility of an African 

 origin for these Philippine species seems thus to be excluded. 



I. Genus BACTROCERA Guerin-Meneville (1830) 1838 



It seems that, for practical purposes, it is still convenient to 

 keep the species with banded wings separate from those with 

 nonbanded wings and thus the following genus is maintained 

 here as distinct; but if the two species with a single crossband 

 on the wings (frauenfeldi Schiner and albistrigata de Meijere) 

 are placed in the present genus, and if the recently discovered 

 African species of Dacus sensu stricto with partly banded wings 

 (hamatus Bezzi and trigonus Bezzi) are taken into consideration, 

 the separation of the two genera seems to be very doubtful. 



* The genus Diplochorda Osten-Sacken, 1880, placed in the Dacinse by 

 Hendel, 1911, and by Edwards, 1915, is now considered as belonging to 

 the Phytalmiidae by Hendel himself, Wien. ent. Zeitung 33 (1914) 74, note. 



9 Atti R. Accad. dei Lincei, Roma V 25 (1916) 425. 



'"Bull. Imp. Central Agr. Exp. Sta. Japan 2 (1919) 92, pi. 2, fig. I. 



