354 HYMENOPTEEA. 



The group of I. volcanicus. 



The keel on the second segment slightly dilated at the base, the remainder acute, sharp ; 



a wide hollow on either side of it; the lateral furrow angled in the middle. Suturi- 



form articulation smooth or finely striated. The other furrows narrow, smooth, 



impunctate. Abdomen and sometimes part of the thorax red or yellow. Wings 



black. (Species 36-49.) 



A. Thorax and abdomen red ; antennae, head, prosternum, and legs black ; wings 

 fuscous. Suturiform articulation not striated. (Species 36.) 



36. Iphiaulax volcanicus. 



Luteus, prosterno, antennis, capite pedibusque nigris ; alis nigris. $ . 

 Long. 13-14 millim. ; terebra 8-9 millim. 



Hab. Panama, Volcan de Chiriqui 2500 to 4000 feet {Champion). 



Antennse less than three fourths of the length of the body, stout, not tapering much 

 towards the apex ; microscopically pilose ; scape as long as the longitudinal diameter 

 of the eye ; apical joint very short, oblique. Face closely punctured, opaque ; a furrow 

 running down from the ocelli ; the lower region and the sides of the head bearing a 

 few longish hairs ; palpi pilose, black. Thorax shining, impunctate. Petiole deeply 

 excavate at the base ; inner furrow wide, moderately deep, the outer furrow separated 

 from it by a high and sharp ridge, the latter itself wider and situated on a lower level 

 than the inner, especially at the base. Second segment with an indistinct keel down 

 the centre at the base, and an oblique, broad depression on either side ; the transverse 

 keel broad, not very deep. Apex of the abdomen pilose, 



B. Abdomen honey-yellow, often black at the apex. (Species 37-41.) 

 1. Suturiform articulation crenulated. (Species 37-40.) 



a. Wings smoky-hyaline, with a large fuscous cloud at the stigma and another at the 

 apex. Apical joints of the palpi fuscous. The keel on the second segment becoming 

 gradually narrower to the apex. Apical third of the abdomen black. (Species 37.) 



^n 37 - Iphiaulax humerosus. (Tab. XIV. fig. 14, $ .) 



Niger, abdominis segmentis l°-4 m flavo-testaceis ; alis fere hyalinis, fusco-bifasciatis, stigmate nigro. $ . 

 Long. 12 millim. ; terebra 11 millim. 



Hab. Guatemala, El Reposo 800 feet (Champion). 



Antennse as long as the body, stout, almost bare. Head shining and impunctate on 

 the top ; the face somewhat opaque, obscurely punctured, sparsely covered with long 



