1921] Giffard: Male Genitalia of Delphacide 137 
NOMENCLATURE OF GENITALIA. 
(See Figures 1, 2 and 8). 
What is apparently the ninth abdominal segment in Delphacidee is 
specialized into a more or less long, chitinous ring (the pygofer (a) ) 
without any clear trace of tergum, sternum or pleura. The posterior 
dorsal edge is more or less deeply emarginate (anal emargination (c) ) 
and more or less surrounds the anal segment (g); the corners of this 
emargination are more or less angular (anal angle (b) ) and in some species 
are considerably produced; the lateral margins (p) vary in shape, being 
straight and entire, produced or excavated; the ventral margin (0) also 
varies in the different species. The relative length and breadth of the 
opening (a, @2) is also important. The tenth and eleventh abdominal 
segments form a small tube (the anal segment (g) ) which lies more or less 
surrounded by the anal emargination (c) of the pygofer. The anus opens 
on this latter segment and below or ventrad of the anus is the anal 
style (h); on the ventral surface of the anal segment are the processes of 
the anal segment (anal processes (i) ) generally in the form of a pair of 
spines. Looking into the opening of the pygofer one sees a more or less 
chitinous wall dividing it into an outer and inner chamber. This is the 
diaphragm (d) the dorsal margin (e) of which is generally V-shaped and 
often in the middle there is developed an armature ( f); near the ventral 
Cardboard 
Glass 
4 
Fics. 1 and 2. m. outer margin of genital style. 
a. ofer; a', a?, opening of offen ui aedeagus (or penis). 
eee length, “ Bho dt. PY8 o. ventral margin of pygofer. 
b. anal angle of pygofer. bp. lateral margin of pygofer. 
c. anal emargination of pygofer. 2D oe of peck 
d. diaphragm. r. orifice of diaphragm. 
e. margin of diaphragm. s. basal angle of genital style. 
f. armature of diaphragm. Fic. 3 
g. anal segment. apg 
h. anal style. n. aedeagus. 
t. anal process of spine. 
k. genital style. Fic. 4. 
/, inner margin of genital style. Details of card mount. 
