AR'1.8. ASHMEAD MANUSCKIPT ICHNEUMONIDAE CUSHMAN. 29 



<SYRPHOCTONUS BILINEATUS Ashmead MS.)==SYRPHOCTONUS VERTEBRATUS Cush- 

 Dian, new species. 



This specimen is Partype h of Sipyhoctonus vertehratus. 



SYRPHOCTONUS VERTEBRATUS. new species. 



" Syrphoctonns bilincatvs Ashin. n. sp.," Si.osson, Ent. News, vol. 11, 1900, 



p. 320. 

 " Himeriosoma quinquecinctum Ashm. MS. n. sp.," Slosson, Ent. News, 

 vol. 13, 1902, p. 320. 



The very striking herringbone pattern of the abdomen, at least in 

 the male, distinguishes this species from any of the described North 

 American species. 



From the male of maculifrons (Cresson), to which it runs in 

 Davis's key, it differs principally as follows : 



Male. — Length, 5 mm. ; antennae, 4.5 mm. 



Face two-thirds as long as wide, narrower than frons; clypeus 

 separated medially from face, elevated basally, and with a short 

 median sulcus at apex; malar space nearly as long as basal width 

 of mandible ; vertex, frons, and temples polished, faintly shagreened 

 but without punctures; ocelli in a rather high triangle, postocellar 

 and ocell-ocular lines equal. Thorax polished, impunctate, though 

 very faintly shagreened laterally on pronotum and on mesoscutum ; 

 scutellar fovea very finely foveolate; propodeum subpolished, finely 

 coriaceous ; second abscissa of cubitus much longer than intercubitus ; 

 discocubitus broadly curved, not subangulate; nervulus interstitial; 

 postnervulus broken above middle, nervellus below the middle; legs 

 very slender; longer hind calcarium reaching barely a third the 

 length of basitarsus. Abdomen narrow ; first tergite equally wide at 

 base and apex, more than twice as long as wide at apex, spiracles 

 very prominent, nearly at middle ; abdomen shining, the basal tergites 

 more or less longitudinally striate basally and shagreened in middle, 

 their apices and the apical tergites polished. 



Black to piceous with the following parts yellow ; mouth, face 

 frontal orbits, scape, pedicel, basal few joints of flagellum, pronotum 

 except brownish stain in middle, propleura, lateral margins and posi- 

 tions of notauli on mesoscutum, scutellum, postacutellum, tegulae, 

 mesopleurum except above, mesosternum, apical spot on first tergite, 

 a large triangular spot on each of the next six tergites having its base 

 at or near apex of the tergite and its apex at or near the base of the 

 tergite, these spots faint on sixth and seventh tergites, venter, all 

 coxae and trochanters, and front and middle femora ; legs otherwise 

 pale testaceous, the hind tarsi somewhat dusky; antennae brown, 

 stigma pale. 



Type locality. — Mount Washington, New Hampshire. 



Type.— C^t. No. 25033. U.S.N.M. 



Described from three males taken by Mrs. Annie T. Slosson. 



