10 
alternation of generations has been established. The small wingless 
form, originally described by Eiley as tritici, is the vernal generation, 
and consists of both sexes. The large winged form, described as grande, 
is the summer generation, and consists entirely of females. The species 
is widespread, occurring through the middle belt of country from the 
Atlantic to the Pacific, and has been reared only from wheat stalks. 
The name tritici Eiley falls on account of its preoccupation by Fitch. 
Dr. Eiley was familiar with Fitch's name, but revived it for the present 
species, thinking with Walsh that tritici Fitch was a synonym of hordei 
Harris. Eiley's name, however, even in that event, would have been 
rejected under the law of "once a synonym always a synonym." The 
dimorphism in this species is fortunate, since it enables us to retain 
Fh;. l.—Itotoma grande Kiley. 
Eiley's name for the summer form as the specific name. The species 
must, therefore, be known as follows: 
Isosoma grande Riley. 
Form grande=winge6 Bummer generation. 
Form minutum ' {proposed in place of tHHd)=wmgleBS spring and winter 
generation. 
Isosoma californicum n. sp. 
Female. — Length, 5 mm.; expanse, 8 mm. Head and thorax rather 
coarsely umbilicate-puuctate; petiole distinct, but short and stout; 
abdominal segments 5 to 8 shorter than 4, 2 and 5 subequal, 3 and 4 
subequal; mesoscutellum pointed at tip, axilla? nearly meeting; meta- 
notuin with a straight central longitudinal groove which is regularly 
concave from side to side and slightly emarginate at borders; each 
side of the groove the metanotum is coarsely umbilicate-punctate; hind 
coxae plainly granulate above. Antenme rather short and stout; joints 
1 For a good figure of form minutum, see Ann. Rept. Dept. Agric., 1881-82, piate xii, 
fig. 3 
