132 PIMPLINE ICHNEUMONIDAE 



Type. — In the collection of the American Entomological 

 Society of Philadelphia. 



The female of this species varies from about an inch to an inch and a haK in 

 length, with an ovipositor about twice the length of the body. The head is 

 yellow, marked with dark-brown or black. There is a dark band extending 

 across the upper part of the head between the front margins of the compound 

 eyes, in which the ocelli are embedded. From this dark band back to the 

 occiput extends a dark brown to black area, slightly lighter in color than the 

 transverse band. From the latter, a dark band extends down to the labrum, 

 where it broadens out, extending to the lower margins of the compound eyes, 

 and thence downward covering all of the lower part of the head in front. 

 The antennae are dark brown to black with the scape and pedicel more glis- 

 tening than the flagellum . The ground color of the thorax varies from brown 

 to black. There is a yellow spot on the side of the prothorax, another beneath 

 the wing, on the side of the metathorax, and on the propodeum just above. 

 In the lighter specimens these propodeal spots may be confluent over the 

 dorsum. The mesonotmn may be brown with black markings, black with 

 ferruginous markings, or entirely black. The mesoscutellum has a square 

 yellow spot in its center and the metascutelliun (generally called postscutellum) 

 has an oblong yellow spot. The wings are hyaUne, tinged with yellow, giving 

 a faint violet reflection in some hghts. The stigma is pale-ferruginous. The 

 legs arg yellow varying with darker shades of the same color. The coxae 

 vary from dark brown to black. The middle and posterior femora are dark 

 with their tips yellow, as are also the tibiae. The tips of the tarsal claws are 

 black. The abdomen is slightly hghter in color than the thorax. Just before 

 the hinder margin of the notum of the second and also of the third abdominal 

 segments is a small transverse yellow band. In the darker colored specimens, 

 reddish-yellow spots are found on the sides of the segments. The spots on the 

 anterior portion of the abdomen are about in the middle of each segment, 

 but they gradually move forward, so that in the posterior segments they are 

 found on the anterior margins. In the lighter colored specimens they are 

 not distinct and form spots only a little Hghter than their surroundings. On 

 each side of the fourth, fifth, sixth, seventh, and eighth segments is a yellow 

 spot, more or less oval in form. The long axis of the spot on the last two 

 segments is nearly at right angles to the body axis. 



In M. nortonii the yellow spots on the sides of the abdomen 

 are rounded-oval, while in the closely related M. lunator and 

 M. greenei they form angled bands. In M. nortonii there is a 

 dark stripe extending from the vertex to and including the man- 

 dibles, in M. lunator there are two dark lines running from the 

 antennae to the mandibles, and in M. greenei these lines are 

 absent. M. nortonii can be distinguished from M. mexicana 

 in that the latter has a pale-yellow ground color, with black 

 markings on the abdomen. The wings of the latter are clouded 



