140 DIPTERA 
Plerempis for the species about fennipes, but for this restricted group the name Emfis should be restored. 
Bezzi's subgenus Emfis should be called Piatyftera, Meigen, since the species borealis, the type of 
Platyftera, occurs there. 
Emfis is the dominant genus of the family, particularly in the Old World with nearly five 
hundred species described it has become very complex. Loew and Kuntze, in a series of papers, have 
subdivided the genus into groups of species centering about a few typical forms.  Bezzi, 1909, effected 
a different separation based mainly on chztotaxy, and designated his groups as subgenera. These 
subgenera are differentiated in the previous table of genera. Their limits are far from definite but in 
the main they appear to be natural groupings. Holopticism appears to have developed in several lines 
of Empis and does not seem to be as ancient a character as Bezzi's definitions would indicate. That is 
to say, the presence of holopticism in Emfis does not of itself bespeak relationship. ; 
The mating habits of several species of EmPis have been studied, particularly by Aldrich and by 
Hamm. Quite often the males have the habit of presenting a small insect to the female who sucks its 
juices during copulation. In the American species aerobatíca the male elaborates a large frothy balloon 
around his prey and flies with this to induce the female to mate. Species of the subgenus Xanthempis 
do not mate in the air. The species of Emfis, s. sir. swarm in shady woods. It is particularly in this 
group that the legs of the females are pennate with scale-like hairs. 
The earliest stages of several species of Em?is are known. Beling has described the larvae of esíiva, 
decora, nodosa, tessellata, and irigramma and Kieffer of meridionalis. The larvze live in rich moist earth, in 
which they pupate following hibernation. They are cylindrical, tapering anteriorly and consist of twelve 
segments, Ventrally they show transverse swellings. The pupa possess bands of abdominal spines. 
Emfis minuta, Fabr. Described in 1787, belongs to PAera, as discussed by Lundbeck, Dipt. 
Danica, Vol. 3, p. 6, 189 (1910). 
SusBGENUS ACALLOMYI!A, NOV. SUBGEN. 
Characters. — Slender, blackish species with long simple legs. Occipital hairs long and 
straggling;; eyes of male contiguous along the front, the upper facets large ; face narrowed ; basal antennal - 
joints short, third joint long and tapering; proboscis very slender, projecting obliquely forward, palpi 
without setze. PProthorax small, mesonotum gibbose, bare of pubescence, acrostichals sparse but 
biseriate, dorsocentrals long, sparse, biseriate, lateral bristles long and hair.ike, one humeral, one 
posthumeral, one presutural, several small notopleural, four scutellar, no propleural, metapleural setze 
bunched. Abdominal hairs sparse, those before the incisures long and delicate, pygidium small. Wings 
normal, third vein curving to end at apex, discal cell not pointed, anal vein incomplete. 
Type species : It«afhila Peregrina, Melander. Emfis brunnca, Coquillett is a closely related but 
distinct species. 
SuBGENUS ANACROSTICHUS, BEzzi 
Characters. — Black, shining or more or less pollinose species of moderate size, with rather 
fine bristles and few hairs. Sex differences slight. Eyes separated, facets uniform, front of male 
sometimes narrower than of female, either parallel-sided or centrally contracted ; head globose occipital 
setule not clearly biseriate; antennz relatively short. Prothorax not bilobate; notal hairs undeveloped 
except a few laterally ; no acrostichals, dorsocentrals almost uniseriate, the three hind ones stronger, one 
humeral bristle and many humeral hairs, one posthumeral, one or two notopleural, two or three presut- 
ural, one or two supra-alar; propleural hairs evident, metapleural long, fine and many, four or six 
scutellars, the inner pair cruciate or convergent. Abdomen bristleless, in the male with rather long 
