Cope.] 1^^ July 16, 



Andeognathid^, Fam. nov. 



A group intermediate between the suborders Strongylia and Sugentia. 

 Characters. The labium a broad slightly cordate plate, extending be- 

 neath the consolidated elements of the front, and having a slight mem- 

 branous marginal attachment externally, leaving a small oval orifice at 

 the anterior extremity. The mandibles rudimental, extremely minute, 

 far v^ithin the margin of the inferior face of the head, composed apparently 

 of two segments. Segments of the body consolidated. Preanal segment 

 an uninterrupted cylinder. 



Andkognathus,* Cope, genus novum. 



GJiar, — Joints of the antennae five, the sixth and seventh confluent, 

 and with the closely joined fifth, forming a club, supported by the shoi't 

 proximal joints ; segments of the body numerous, (over fifty in the only 

 species,) muzzle short. 



This singular genus is one of the hitherto unknown forms connecting 

 the suctorial group of Myriapoda with the mandibulate. It furnishes a 

 clue also to the structure of the suctorial mouth of the former group, 

 which appears to have been as yet unexplained. Thus we see that the 

 mandibles disappear, and the labium extends, and uniting by its margins 

 on either side leaves the mouth a transverse fissure. With a fvirther 

 union of the mandibles with a prolonged labrum on each side, we wovild 

 have a form of Sugentia, perhaps like Brachycybe of Wood, between 

 which and the Polydesmidae the present genus stands. Like many of 

 the members of the latter family, this one occurs under bark of decaying 

 logs, though its food is more probably of a soft character, as the de- 

 composing fungi often found in such situations or the bodies of dead in- 

 sects and molluscs. 



Andrognathus corticarius, Cope, sp. nov. 



This is a rather slender and cylindric species with fifty-six segments, 

 having rather short, strong, lateral laminae projecting abruptly from all 

 except the anal. The dorsal i3ortion of the segment is convex above the 

 lamina, but less so than the ventral. The anterior laminae are transverse 

 but the majority have an oblique anterior truncation. Non sheathing 

 part of each segment slightly convex, and divided on the median line by 

 a groove, within which runs a delicate thread or bead, which is raised 

 on the lower part of the segment, and extends throughout the length. 

 Upper surface of segment also divided transversely by one annular groove, 

 the raised portions being minutely rugose. The same rugosity exists 

 below the laminae. The anterior shields and laminae at least, have a fine 

 pubescence. The antennae and front are densely pubescent. Labral 

 margin flat, not emarginate. The muzzle is not so long as the antennae, 

 and less contracted than in Wood's figure of Brachycybe. Anal annulus 

 elongate, smooth, truncate, enclosing the short lateral anal plates. Length 

 nine lines ; proportions slender. Color in life, a very pale yellowish 

 brown, lighter below. 



From Montgomery County, Virginia. 



* a'^fjp man, y^aOoq jaw. 



