92 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



incrassated on basal third: Two pairs of orbitals present. Cheeks black ; 

 thinly grayish pollinose not wider than one-sixth eye height, transverse 

 impression silvery. Inferior occiput swollen, superior linear, silvery, head 

 wider at vibrissse than at base of antennse. Paipi yellowish. Intermediate 

 third of proboscis cylindrical, black, chitinized, apical third fleshy, yel- 

 lowish, entire length slightly greater than height of head. 



Thorax shining black, marked with three short, silvery, pollinose vittse 

 one over each humerus and one median in a similar manner to Morelia micans. 

 Scutellum triangular, shining black, bearing three pairs of marginals and a 

 strongly cruciate apical pair. Dorso-central bristles three, sternopleurals 

 two. Abdomen slender, shining, absolutely bare of pollen, five segments 

 visible, the first quite short and black. Second and third segments orange 

 yellow, bearing a median black vitta which does not reach the anterior or 

 posterior margins in the latter. Fourth segment somewhat wrinkled 

 transversely, dark yellow, marked with a broad black median vitta ex- 

 tending to the lateral margins at the apex of segment. Fifth segments 

 (figs. 3-4) shining black, wrinkled, with a triangular depression in the 

 center upon the margins of which are borne some short black spines, apex 

 provided with the usual stout forceps as shown in the figures. 



Segments two to four inclusive, bearing stout median and lateral mar- 

 ginals. No discals present on any segment. Legs rather long and stout, 

 middle tibise bearing three strong macrochseta3 on front side near middle. 

 Posterior bearing two outside and two inside near middle, apical tibial spurs 

 unusually long and stout. 



Wings narrow, slightly infuscated along costal margin. Costal spine 

 present but small. Veins yellowish at base, black at apex. Bend of fourth 

 vein very slightly angulated, apical cell barely open in margin. Hind cross 

 vein enters fourth vein much nearer to bend than to small cross vein. Angle 

 with fifth vein about 115 degrees. Calypters whitish. 



Male: Differs from female as follows: larger, strongly resembles male 

 of Leucostoma. Orbital bristles absent, head (fig. 5) wider than thorax 

 and large in proportion to body. Front very narrow, bare excepting a 

 single row of f rentals. Third antennal joint about one and one-half times 

 longer than second. Palpi slender nearly black. Abdomen more ovate, 

 black, longitudinal median bands of second and third segments broader 

 and continuous. Fourth segment sometimes almost entirely black, showing 

 a mere line of yellow on lateral margins. Ordinary vestiture of the abdo- 

 men longer and more erect than in female. Venter yellow with a narrow 

 black median vitta. Hypopygium barely visible, black. The bend of the 

 fourth vein is subject to considerable variation in this species, in some 

 specimens it is gently rounded, others have it slightly angulated, one of 

 the latter, a male, bears a distinct short stump at the bend. 



Described from seven specimens, male and female, collected at 

 Salt Lake, Utah, May 15 to 21, by P. H. Timberlake of the Bureau 

 of Entomology and in honor of whom this species is named. Two 



