138 Annals Entomological Society of America [Vol. XIV, 
edge or margin (0) of the pygofer the diaphragm is pierced by an orifice 
(r), through which the genital styles pass. The length of the diaphragm 
is from the dorsal margin in the middle to the orifice. In the Delphacidze 
there is always one pair of genital styles (k) which are of various size 
and shape; the terms inner (lJ) and outer (m) margins are of use in 
descriptive work, also the basal angle (s). The aedaegus (n) arises from 
the bottom of the inner chamber and when at rest its apex generally 
projects over the middle of the dorsal margin of the diaphragm, just 
above the armature. There is an internal structure connecting the 
anal segment to the base of the genital styles, which can be termed the 
connecting structure. 
THE DISSECTION AND TREATMENT OF THE PYGOFER AND 
GENITAL ORGANS. 
For ordinary purposes, when comparing the margins of the pygofer 
and exposed genital organs of a species under examination with any 
illustration or figure, the binocular microscope is much preferable to 
the hand lenses ordinarily in use and students should by all means 
use the former when possible. The size and opaqueness of these organs 
in very many of the species are such that in careful systematic work 
even the binocular, without an electric illuminator or condenser,* is 
insufficient to secure a proper and correct view of their structure. With 
an abundance of material to choose from, one might, on occasion, 
select an example which would result satisfactorily without the illumi- 
nator, but otherwise the student is quite apt to draw wrong conclusions. 
The structures of the genital organs contained within the aperture of 
the pygofer are, as previously stated, of the greatest importance for 
correct, determination of the species and these must therefore not only 
be viewed by the observer under the best of conditions, but on occasion 
the aedeagus, genital styles and anal tube must be dissected out. The 
aedeagus itself is so hidden behind the diaphragm of the pygofer that it 1s 
seldom visible, even with the strongest of illuminations and magnifica- 
ton. + The anal tube, whilst visible, in a measure, with the hand lens 
or-binocular, has in very many instances spines or processes of various 
lengths attached to its medio ventral surface, which are either quite 
invisible or are obscured by the genital styles. In many instances 
specimens, as ordinarily viewed; have their genital styles resting at a 
different angle than when they are normally at rest, which fact is quite 
sufficient to alter the outline and lead to error. This can easily be over- 
come if the styles are dissected out and a flat view taken. 
The dissection of the genital organs is simple, if reasonable care is 
used. The method adopted by Mr. Muir and the author is to carefully 
sever the pygofer from the abdomen, transferring it to a 50% or 60% 
solution of Caustic Soda and boiling it over an alcohol flame in an 
* The author has used with much success the B. & L. micr. lamp with aspheric 
condenser and transformer for 110 V. alternating current. The smaller and cheaper 
B. & L. illuminator and condenser has not been altogether satisfactory for this 
special work. 
