496 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
TIDOPS SIMUS, sp. nov. 
General color ochraceous. Head and prosternum dark reddish — 
brown or ferruginous. Legs yellow. . 
Head with median sulci showing as two short parallel lines across 
caudal border. Head differing slightly in width anteriorly and pos- — 
teriorly; anterior margin widely semicircular; caudal margin sub- 
truncate or but slightly excurved. 
Antennae flattened, composed of thirteen articles of which the first — 
two, three, or four are very sparsely hirsute, the others becoming — 
gradually more and more densely and finely clothed with short straight — 
hairs of the type usual in the family. 
Claws of prehensors dwarfed. None of the articles of prehensors ‘ 
armed within. 
Prosternum with two deep and continuous submedian longitudinal — 
sulci. Anterior margin bearing two large, cylindrical, distally rounded 
teeth or dentiform processes. 
Transverse sulcus of first dorsal plate strongly bent back in an angle ~ 
at middle, the vertex lying in a rather deep depression or pit; sulcus 
wholly free from the cephalic plate. Longitudinal sulci subparallel or _ 
a little converging cephalad from the caudal margin to about two thirds — 
the distance to the transverse sulcus where each bifurcates, sending its 
mesal branch to meet its mate at the angle of the transverse sulcus and 
its outer branch ectocephalad to meet the transverse sulcus farther — 
laterad. Dorsal plates from the second one caudad longitudinally 
bisuleate. Lateral furrows distinct from the fifth plate caudad. Me- 
dian keel low and flat, set off by furrows on the posterior plates, but 
becoming first indistinct and finally disappearing cephalad. Last 
dorsal plate with margin bowed out caudad as usual; the margin 
mesally truncate. With a median longitudinal sulcus. 
Ventral plates long, longest cephalad, a little incurved near middle; — 
more strongly narrowed caudad, the tongue-like, distally rounded 
caudal end lying well beneath the anterior portion of the succeeding 
plate. Widely but distinctly depressed transversely across middle of 
plate, but with no evident longitudinal furrows or sulci. Last ventral 
plate narrowed caudad. Caudal margin mesally indented or emargi- — 
nate, the emargination very obtusely angular with the margin each 
side convex and the corners rounded. A pair of bristles on caudal 
portion. 
Process of coxopleura rather short, acutely one-pointed. No spines 
proximad of tip of process or on caudal margin of coxopleura, but a- 
stout bristle at base of each process. Pores of small size, numerous; 
the pore area not fully attaining the caudal margin, and removed from — 
lateral margin caudally by a wide space but only by a narrow space 
anteriorly. 
