182 DIPTERA 
of species results. A day's collecting in the haunts of these insects has rarely failed to produce a new 
form. I have before me several hundred undescribed species of RhamfAomyia, and as the number of - 
combinations of possible characters is far from being exhausted, it can be stated that we are just beginning 
our acquaintance with these interesting species. 
Whether RAamfhomyia is a monophyletic or a polyphyletic group is unsettled. The trend of 
evolution in the genus is paralleled to a great degree by species of Em?is. The pennate structure of the 
legs of the females, the development of ventral prongs on the abdomen of the male, the structure of his 
pygidium and of the knee armature, the tendency to holopticism and the reduction or amplification of 
the bristles may be the result of convergent evolution or may indicate that the various groups of species 
we call RAamfhomyia are offshoots of the subgenera of Emfis, specialized by a simplification of the 
third vein. Richard Frey of Helsingfors has recently published a segregation of this complex group 
into subgenera. His study was based mainly on palzarctic species and accordingly his groups do not 
adapt themselves as readily to the tropical forms as they do to the nearctic species. The divisions 
proposed by Dr. Frey are based mainly on the arrangement of the notal bristles, character of axillar 
incision of the wing. form of pygidium and contiguity of the male eyes. The subgenera are diagnosed 
below and a list of species assignable to each is given. The list is obviously incomplete, being made 
up from Frey's paper and such additional species as are before me. Some species, like R. cyanogaster, 
Wh. & M., Pulchriventris, Bez., Sauferi, Bez., and tolteca, Wh. & M., do not agree well with the 
subgenera as defined 
SuBcGENUS DASYRHAMPHOMYI!A, FREY 
Characters. — Males rarely dichoptic, the eyes usually broadly contiguous; ocellar triangle 
developed; antenna not excessively lengthened. | Body rather stout, usually dull in color, dorsocentrals 
usually weak and pluriseriate, acrostichals present, scutellars many. — Pygidium characteristically of two 
types, either with a long erect vesiculate structure, or small and closed, broadly deformed, with the 
seventh tergite convex and usually set in the wide sixth tergite, in the latter case armed with two prongs 
below and the last sternite usually fringed with two bunches of yellow setze. — Legs rather strong, rarely 
pennate in female, the hind femora rarely setose below. Wings commonly broad and brown in female, - 
axillar incision usually acute. 
Type species : R. vesiculosa, Fallen. Additional species include: R. Brussnevi, Frey, conservativa, 
Mall., coracina, Zett., Hambergi, Frey, Hoovgaardii, Holmgr., mirifica, Frey, nigrita, Zett., Pokornyi, Bez., 
reflexa, Zett., vara, Lw., vesperlilio, Zett., virgata, Coq. and W'uorentausi, Frey. j 
SuBGENUS HOLOCLERA, ScHINER 
Characters. — Males holoptic, ocellar triangle and bristles evident; antennz not greatly 
lengthened. Small species with slender body, sometimes differing in color in the sexes, sometimes 
yellow in both male and female; dorsocentrals uniseriate, acrostichals present or absent. Pygidium 
small and closed. Legs slender. Axillar incision of wing ranging from obtuse to rather acute. 
Type species : R. uigripennis, Fallen. Other species, all from the palearctic region, include : 
R. culicina, Fall., flava, Fall., flaviveutris, Macq., heterochroma, Fab., pallidiventris, Fall., sciarina, Fall., 
tenuirostris, Fall. and umóripennis, Meig. 
SuscENUS LUNDSTROEMIELLA, FREY 
Characters. — Males dichoptic, the ocellar triangle not elevated, ocellar bristles very weak; 
antennz greatly lengthened, nearly twice as long as the head, the third joint excessively long. Body 
