64 SEVENTEENTH REpoRT STATE ENTOMOLOGIST OF MinnNeEsota—1918 
usually short, spine-like and sharply pointed. | Spuriae rarely with 
sensoria on the third segment of the antennae. Prothoracic and lateral 
tubercles usually present. Cornicles cylindrical, sometimes swollen in 
the middle, rarely short and wanting; reticulation open and not form- 
ing closed cells as in Macrosiphini. Cauda cone-shaped, triangular or 
pointed with a basal clear area. 
Biological characters. Size medium to small, never very large 
as the Macrosiphini. While some are found on succulent twigs and 
leaves of woody plants from which they usually migrate to herbs for 
the summer generations, returning in fall to the primary host plant to 
oviposit, most of them develop altogether on herbaceous plants. The 
variety of plants inhabited is very great; the largest number is con- 
fined to a single or at most a few closely related plants. Some seem to 
feed indiscriminately on a very large number of different plants. 
hs eme MY Z UNG 
Morphological characters. Front concavity narrowed, especially 
in the larval forms, due to the glandular swellings on the inner side 
of the usually short frontal tubercles, which are strongly reticulated 
and provided with capitate sensilla like those on the antennae. 
Antennae usually much longer than the body; sensilla sometimes very 
short but distinctly capitate. In the larval forms the hairs of the body 
are also capitate, at least those on the front of the head. Cornicles 
Jong and cylindrical, usually club-shaped or enlarged near the apex. 
Cauda much as in the Aphidint. 
Biological characters. In habitat the present tribe agrees in gen- 
eral with the Aphidini and Macrosiphini, but the presence of capitate 
hairs on the body in the larval forms indicates a different line of 
development and origin from the other two. Similar conditions of 
sensilla are found in the Callipterina, with which the Myzini may be 
considered to converge, or it is possible that they have diverged from 
a common stock of the past. 
12. Trrme MACROSIPHINI 
Morphological characters. Front deeply and broadly concave, 
antennal tubercles usually distinct. Antennae usually much longer 
than the body; sensilla usually long and spatulate or widened spear- 
like at apex. Sensilla on the head and body usually hair-like, the 
same as in larval forms. Cornicles cylindrical, sometimes widest 
in the middle; reticulation closed, forming cell-like arrangement on 
