578 
GENETICS: A, M. BANT A 
The experiment was also made of crossing the spectra at some other 
angle than 0° or 180°. For instance, the rulings of the Ives grating 
were placed at right angles to those of the interferometer grating, as 
in Newton's method of crossed prisms. Seen in the telescope (adjusted 
for inverted spectra) the two spectra now made an elbow with each 
other, while the Di Z>2 lines were still parallel and could be put in coin- 
cidence. On using a long (meter) collimator, strong interferences were 
obtained in the line of symmetry of the elbow and normal to the D 
lines. They have the same characteristics as the preceding and persist 
during a displacement of mirror of about 0.3 cm. 
SEX INTERGRADES IN A SPECIES OF CRUSTACEA 
By Arthur M. Banta 
STATION FOR EXPERIMENTAL EVOLUTION. CARNEGIE INSTITUTION OF WASHINGTON 
Received by the Academy, August 30, 1916 
In unisexual forms we are accustomed to think of the term male as 
signifying the possession by the animal indicated not only of a sperm- 
producing organ and the associated accessory male reproductive struc- 
tures but also of certain definite secondary sex characters, definite 
characters of form and structure and, further, of conspicuous physio- 
logical and psychological characteristics. The term female implies 
definite and marked characters contrasting with those of a male on all 
these points. In other words maleness and femaleness are generally 
taken to indicate definite and precise opposed and alternative states, 
only one of which may obtain in a single individual. 
The occurrence of known deviations from the conditions of male- 
ness and femaleness are in the main confined to a comparatively few 
isolated and sporadic cases of hermaphroditism and gynandromor- 
phism. Gynandromorphs are really sex mosaics inasmuch as a definite 
portion of the body, frequently one-half, possesses in toto the definite 
characters of one sex and the remainder of the body is distinctively 
of the other sex. However two workers have published concerning 
stocks in which considerable numbers of individuals are intermediate 
in their sexuality— intermediate not as sexual mosaics but quanti- 
tatively and as a whole different from either the normal male or the 
normal female. Riddle^ has demonstrated intermediate sex forms in 
his pigeons and Goldschmidt has obtained such forms in the offspring 
of certain crosses in the gypsy moth. 
In a species of crustacean the writer has obtained intermediate sex 
forms (for which the term sex intergrade seems appropriate) constitut- 
