JOURNAL OF ENTOMOLOGY AND ZOOLOGY 25 
ments together, the second segment not quite as long as the 
two following united; claws with a tooth within. 
Cornus rather long, but abnormally wide at base, barely con- 
stricted in the middle, not altogether unlike the cornus of Sirex 
areolatus; ovipositor extending a little more than twice the 
length of the cornus beyond the tip of the latter. 
Length of the front wing 15 mm.; of the cornus 2.7 mm.; of 
the ovipositor 15 mm.; total length 20.5 mm. 
It gives me pleasure to dedicate this species to my friend and 
former teacher, Dr. A. D. MacGillivray, in recognition of his 
signal contributions to our knowledge of the Chalastogastra. 
Tremex Jurine 
Tremex, gen. tremicis, M. irr. <Tphpa<tetpaivw—toborethrough. derivatives: tremic +- 
(Figs. 3, 9, 16, 36, and 38) 
<1761 Sirex Linneus. Fauna sueice; ed. 2: p. 396. 
<1762 Urocerus Geoffroy. Hist. abreg. insec. d. Paris; v. 2: p. 264. 
1807 Tremex Jurine. Nouv. meth. class. Hym.; p. 80. 
1837 Xyloterus Hartig. Fam. d. Blatt. u. Holzwespen.; p. 385. 
1868 Xyloecematium Heyden. Ueber das seither unbek. < Manchen 
von Xyloterus fuscicornis. < Berl. ent. Zeitschr.; v. 12: p. 27. 
There is only one North American species. 
Tremex columba (Linneus) Lepeletier de Saint Fargeau 
There are three fairly well marked races, of which heretofore 
only two have been recognized. 
A Key To THE Races or TREMEX COLUMBA 
A. Entire body fulvous; legs beyond femora yellow; wings dark red- 
dish brown. Race sericeus Say. 
AA. Abdomen marked black and yellow. 
B. Ground color black; second dorsal segment, line at base of 
third, broadened laterally, wedge-shaped spot on sides of 
five following segments, the cornus at base, and sometimes 
spot on sides of ninth segment yellow; head and thorax 
varied with brown; wings brown or yellowish. 
Race columba (Linneus) Lepeletier de Saint Fargeau 
BB. Ground color yellow; apical line of second to seventh dorsal 
segments; sometimes apex of eighth and more or less of 
sides of ninth segments black; head, thorax and antennie 
yellowish brown; wings yellow. Race aureus new race 
