108 U. S. NATIONAL MUSEUIVI BULLETIN 216 parts 



0.5 ± of last segment usually white ; segments 2-4 of hind tarsus white; 

 abdomen fulvous, tergites 5-7 infuscate, the fifth often more or less 

 ferruginous, the seventh and sometimes also the sixth and even the 

 fifth with a median apical white spot; occasionally the first four 

 tergites have some infuscate areas. 



Female: Head black, the frontal and facial orbit often white or 

 partly white, face and usually clypeus blotched with brownish, and 

 cheek and lower part of temple with a very large white mark; palpi 

 fuscous, the maxillary palpus and sometimes also the labial palpus 

 white subbasally; antenna black, the scape brownish and flagellmn 

 with an incomplete white band that covers about 4 segments; pro- 

 pleurum black, usually with a ventral ferruginous stain; pronotum 

 black, the collar, stripe along lower margin, and hind corner white; 

 mesoscutum black; tegula, subtegular ridge, scutellum, and post- 

 scutellum, white; areas near scutellum and postscutellum black; 

 prepectus partly fuscous, partly ferruginous; mesopleurum, mesoster- 

 num, metapleurum, and propodeum ferruginous, the mesopleurum 

 near subtegular ridge, usually sternaulus, and usually median 

 stripe on mesosternum, infuscate; front coxa white and brown or white 

 and ferruginous; middle coxa ferruginous, sometimes partly white; 

 hind coxa ferruginous; trochanters ferruginous, usually brownish 

 above, especially the front and middle trochanters; front and middle 

 legs ferruginous, the fifth segments of their tarsi bro\\Ti; hind femur 

 ferruginous, its apical 0.12 weakly infuscate; hind tibia and basitarsus 

 brownish ferruginous, the tibia paler basally; segments 2-4 of hind 

 tarsus white, or sometimes partly brown; segment 5 of hind tarsus 

 dark brown; abdomen ferruginous, the fourth segment rarely partly 

 infuscate, the fifth and following segments fuscous, the seventh with 

 a median apical white spot. 



In general structure, especially in the obsolesence of the dorso- 

 lateral carina of first tergite between its spiracle and base and in 

 the close spacing of the teeth on apex of ovipositor, this species 

 resembles A. linnae, an undescribed species from China, and the 

 European A. signatoria. (Aritranis signatoria (Fabricius) is a new 

 combination, from Ichneumon signatorius Fabricius.) The species 

 gracilis and signatoria are known to parasitize nests of aculeate 

 Hymenoptera in twigs. Linnae and the Chinese species may have 

 the same habits. 



Specimens (78 c?, 349): From Maryland (Glen Echo and Takoma 

 Park); Michigan (Ann Arbor, George Reserve in Livingston Co., 

 Midland Co., and Ontonagon Co.); New Jersey (Haddon Heights and 

 Moorestown); New York (Babylon, Bemus Point, Canajoharie, 

 Farmingdale, Ithaca, Orient, Peru, Poughkeepsie, South HiU near 

 Ithaca, and Taughannock Falls); North Carolina (Hamrick, and 



