588 MISC. PUBLICATION 657, U. S. DEPT. OF AGRICULTURE 
and yellowish white and have a small spine at the posterior end of the 
body. They are wood borers. Some of the species may have one 
generation annually, whereas in other species it may take 3 years to 
complete a generation. 
SUBFAMILY TREMICINAE 
The adult female of the pigeon tremex (Co eaice columba (U.)) 
(fig. 172) ranges from 11% inches to about 2 inches in length. The 
Neel antennae, and thorax are reddish and black, and the abdomen 
is cylindrical and black, with ochre yellow bands and spots along 
the sides. The horned tail at the hind end of the body, which is 
merely a sheath for the boring structure of the ovipositor, is yellowish. 
The legs are dull yellow. The wings are smoky brown and re 
2 or more inches. The male is reddish, varied with black, 34 to 114 
inches in length, and the abdomen is not furnished with a pores but 
ends with a conical horn. The larva is whitish, cylindrical, and about 
2 inches in length when full grown. The thoracic legs are fleshy, not 
well formed and not jointed. There are no abdominal legs. The ab- 
domen terminates in a prominent short brown process which is str ong- 
ly sclerotized and compressed, and has two pairs of small but distinct 
teeth, 
FIGURE 172.—The pigeon tremex (Tremexr columba): A, Larva; B, head of larva, 
enlarged; C, pupa of female; D, pupa of male; H, adult female. 
