258 MISC. PUBLICATION 657, U. S. DEPT. OF AGRICULTURE 
Control measures given on page 38 should be followed. 
Orthosoma brunneum (Forst.), the brown prionid is a large. elon- 
gate, flattened beetle from 22 to 40 mm. long, dull reddish brown, with 
the sides of the prothorax margined and Dearing three sharp teeth. 
The larvae are elongate, cylindrical, and of very shining texture. The 
head, wider than long, is retracted into the thorax, and has the front 
produced in two transverse, sharp-edged, dentate carinae. The dorsal 
ampullae bear two transverse impressions. Legs are present. These 
insects feed gregariously in coniferous or hardwood trees that have 
been dead several years in moist situations, making large mines packed 
with coarse fibrous frass. They are found in the Atlantic States and 
the Middle West. 
Like other prionids, the adult flies late in summer after the flower- 
ing of the chestnut. The female inserts her eggs in the wood of tim- 
bers that have been dead for several years. The larvae make exten- 
sive excavations tightly packed with coarse fibrous frass. When they 
feed in large numbers in moist heartwood, little is left of the or iginal 
wood. Ove erly wet wood is not favorable to the feeding of this insect. 
The pupal cell, deep in the wood, is plugged behind w ith fibrous frass, 
the opening to the exterior being made by the adult. Under favor- 
able conditions the larva matures and pupates within 2 years, but 
more commonly 3 years is required.. About 1 month is passed in the 
pupal stage. Cross ties, telephone poles, and all structural timbers 
in contact with the ground or in moist exposed situations are subject 
to injury by this insect. Since several generations continue to feed 
in the same timbers and because the larval mines are so extensive, seri- 
ous destruction follows. Control may be effected by the methods 
given on page 43. 
Parandra brunnea (F.), the pole borer, is an elongate, oblong, some- 
what depressed, brown beetle, from 9 to 18 mm. in length. The pro- 
thorax is subquadrate, having the sides and wing covers margined. 
The fourth joint of the tarsus is distinct. The larva is elongate, 
shghtly tapering posteriorly, having the head wider than long “and 
retracted into the prothorax. The “mandibles are sharply pointed. 
The pronotum is coarsely asperate, the ampullae are finely wrinkled, 
and the legs are developed. This larva bores gregariously in the 
dead, but moist, heartwood of practically all hardwood and many 
coniferous trees in contact with the ground and also in cavities in 
living trees throughout the United States east of the Rocky Mountains. 
The adult appears shortly after the blossoming of the chestnut, 
laying a large number of eggs deep in any exposed heartwood. In 
this wood the larvae feed gregariously for 3 or 4 years, completely 
honeycombing it and packing the mines with granular frass. The 
oval pupal cell constructed in the wood is plugged behind with a 
wad of fibrous frass. Pupation takes place about a month before the 
adults emerge. This is one of the most destructive borers attacking 
shade trees, cross ties, telephone and telegraph poles, and any struc- 
tural wood in contact with the ground or in moist situations. A small 
wound near the base of a living tree may offer a place of entrance for 
the young larvae, which will continue to feed in the heartwood until 
nothing remains but a shell of sapwood. Under certain circumstances 
the adults do not emer ge but mate and lay eggs in the same cavity 
in which they are working. Often the wound where they gained 
