1921} Metcalf: Gemitalia of Male Syrphide 207 
EXPLANATION OF PLATES. 
ABBREVIATIONS AND GLOSSARY. 
Except in Figures A to H, Roman numerals are used to indicate the successive 
urites, both for the tergites and for the sternites. 
Caudtnt ll... 2. Caudal internal lobes. 
GE Mare x66. ao Cercal emargination, the emargination at apex of tergite ten, 
into which the cerci are received to a varying degree. 
Gephe sk aos as x Cephalic emargination, an emargination on the cephalic face of 
the penis sheath near the apex. 
Reon Int. Wo... Cephalic internal lobe. 
(CCH ey ha ee Cercus. 
(Ca a Chitinous box, a chitinous mass at the apex of the penis through 
which the ejaculatory duct may pass and to which are articu- 
lated or joined the ejaculatory hood, the ejaculatory process 
and the internal lobes. 
Ejac. Apod........Ejaculatory apodeme, a chitinization attached to the ejaculatory 
sac. 
Biae: Deter. sete: : Efferent ejaculatory duct. 
Bae. Maid (oP. a 8: Ejaculatory hood, a projection from the chitinizations sur- 
rounding the ejaculatory duct which stands caudad of the 
ejaculatory duct on the median line. 
Ejac. Pr...........Ejaculatory process, a prolongation from the chitinous box. 
which surrounds the ejaculatory duct in cases where the 
orifice of the duct is elevated above the chitinous box. 
Bjac. Sac..........Ejaculatory sac. 
(Giy RASe oea anes ol oaae Genital pouch, a depression near the apex of the venter of the 
abdomen, into which the penis, styles, etc., are received when 
not in use. : 
Inf. Lob...........Inferior lobe, the more cephalic of two pairs of lobes or append- 
ages arising from the apex of the penis sheath. 
ateOb ease ese: Internal lobe, one of two pairs of lobes or appendages associated 
with the chitinous box or with other chitinizations about the 
ejaculatory duct. 
Lingula............A median tongue-like process from the apex of the penis sheath 
on its cephalic face. 
L. Caud. Int. L.... Left caudal internal lobe. 
Re Cet... bees Le) b CELGUS: 
L. Inf: Lob........Left inferior lobe. 
A Sie oo ee ee Spiracle of the left side. 
Ws SHOE ILO eno - Left superior lobe. 
Postabdomen.......The caudal four or five urites of the abdomen that have been 
greatly modified in conformity with the genital appendages. 
Post-anal Hood..... A median ornamental expansion standing caudad of the anus 
and between the styles. 
Preabdomen........ The unmodified, four or five urites of the cephalic part of the 
abdomen. 
R. Caud. Int. L.... Right caudal internal lobe. 
RVC Citi) aye Right cercus. 
R. Ceph. Int. L.... Right cephalic internal lobe. 
R. Inf. Lob........ Right inferior lobe. 
[Pe Sa Spe eee oe Spiracle of the right side. 
RESIS GY;crtest ote ee Right style. 
pup.) Leap... l¢ Right superior lobe. 
Me ota aca OE Sternite. 
BORN ecard. oki acad Sapte Scutellum. 
SION os 205 As we Ler Mele. 
SUM Ahad tenes ee Style. 
