The color of this species is a very dark brown, sometimes with a reddish, sometimes with an olive or even bluish tint. The head is quite deeply emarginate. The vertex furrow is pronounced. The first scutum is margined with deep red both anteriorly and posteriorly. The posterior borders of the other scuta are furnished with a narrow, dark brownish, red margination.
Fig. 35
The male appendages (Fig. 35) are formed of two outer parts and the yoke-like piece
which connects them. The former are composed of the following parts:
First. A thin plate bent around the inner portion; this is deeply
notched laterally, but presents on one aspect a long, low, smooth surface; on the other it is produced into a broad process, rapidly narrowing and terminating distally in a very narrow, blunt portion, which is
abruptly bent on itself, but does not form a hook. Next within this
is a large, thick, blunt, curved process, composed of a plate so bent on
itself as to make a sort of sheath, in which lies a thin, flat, blunt,
slightly falciform process.
Hab. United States.
M. Girard has described two species of lulus from the Southwest, atratus and ornatus. His description of the latter applies to I. marginatus. I have seen the type of I. atratus, but unfortunately in such a bad state of preservation that I am unable to decide with certainty its claims to rank as a species; it is, probably, however, nothing more than a variety. The descriptions of M. Girard are given below in full.
I. ornatus.
"Spec. Char.—Ground-color bluish black; segments narrowly margined posteriorly with reddish; anterior margin of segments rather blue, whilst the middle is rather black, thus giving the appearance of three rings of color. The anterior portion, which is covered by the articulation, is fulvous. Feet deep chestnut-brown. Antennae rufous at base, blackish at tip. Stigmata not conspicuous, marked by a series of small obsolete blackish spots."
"Remarks.—This species is allied to Iulus marginatus of Say, but the body is proportionally much stouter. The ocelli are disposed upon a subtriangular space quite different in shape. The antennae themselves are slenderer in proportions. The labrum (upper lip) is also less emarginated than in Iulus marginatus, and the marginal punctures much less conspicuous."
I. ornatus, Girard, Marcy's Report, Exploration Red River of the South, p. 274.
I. atratus.
"Spec. Char.—Body, feet, and antennae, uniform deep blackish brown; antennæ and feet
