hooks along the anterior margin by which they are attached to 
the front wing. Some forms, such as the common ant, are wing- 
less. The ovipositor is usually well-developed and in the higher 
forms is modified into a sting. 
The order is divided into two suborders—Anocrita (=—Clisto- 
gastra) and Symphata (=Chalastogastra) (550). Each of these, 
in turn, is divided into a number of superfamilies. 
Suborder SYMPHATA (— CHALASTOGASTRA) 
Members of the suborder Symphata are distinguished by hav- 
ing the abdomen of the adult broadly joined to the thorax—the 
first abdominal segment is not modified into a petiole as in the 
suborder Apocrita. The ovipositor of the female is well-developed 
and fitted for making incisions in the leaves or stems of plants. 
In the majority of species it is saw-like. Because of this, these 
members of the suborder are known as sawflies. 
The larvae of all species, except for the family Orussidae, are 
phytophagous, the majority feeding externally on the foliage. The 
remainder bore into stems, fruit, wood, or leaves to feed. Orussid 
larvae are parasitic on wood-boring coleopterous larvae. While 
external leaf-feeding larvae look like lepidopterous larvae, they 
have only one ocellus on each side of the head and have six or 
more pairs of prolegs on the abdomen, none of which bear hooks 
or “crochets.” 
The suborder Symphata is represented in the United States 
and Canada by approximately 1,000 species, many of which are 
highly destructive of forest and shade trees and of young trees in 
nurseries and plantations. 
SUPERFAMILY MEGALODONTOIDEA 
Family XYELIDAE | 
Members of the family Xyelidae are medium-sized to small 
sawflies, most less than 19 mm. long. They differ from all other 
sawflies in having the third antennal segment longer than all of 
the remaining segments combined and in having three marginal 
cells in the forewing. Unlike all other sawflies, except the Pam- 
philiidae, they have the costal cell divided by a longitudinal vein. 
The genus Xyela Dalman contains several species which feed 
as larvae on the developing pollen of the male strobili of various 
species of pines. The adults are usually found on the catkins of 
willow and alder and occasionally on the pollen of pines. Only 16 
species are known in the world (119). X. baker1 Konow—reared 
or collected from longleaf, slash, and jack pine (known to occur 
from Maryland to North Carolina as well as in Florida and 
Texas) ; X. minor Norton—known hosts are Virginia, slash, and 
longleaf pines (in Virginia and from Florida to Texas) ; X. ob- 
scura (Strobl)—known hosts are jack, Virginia, slash, and long- 
leaf pines from southern Canada to Florida and Texas); X. 
alpigena (Strobl) —recorded from white pine and spruce (south- 
ern Canada, New York, Maryland, and Illinois) ; X. styrax Bur- 
dick—recorded from Virginia pine (Maryland and Virginia). 
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