12^ Mr. H. W. Bates on the 



wings. The thorax is smooth and glossy^ with five promi- 

 nent tubercles on the disk. The eyes in the male do not reach 

 the median line of the front ; in the female they are separated 

 by a space about twice the width of that of the male. The 

 elytra are strongly subuliform. The metasternum is very 

 voluminous, and the abdomen very slender, especially at the 

 base, in both sexes. In the male the apical ventral segment 

 is concave in the middle and elevated at the sides. 



A single male in Dr. Baden's collection has two strong 

 spines at the apex of the fourth ventral segment, like the male 

 of Acyjjhoderes femoratus. In two other males there is no trace 

 of this armature. The terminal ventral segment in the speci- 

 men mentioned has not the concavity and lateral wings of the 

 type. As the form and colours of all the specimens are 

 exactly similar, I do not venture to consider these sexual 

 differences specific. 



3. Isthmiade ichneumoniformis. 

 Isthmiade ichneumoniformis, Bates, Trans. Ent. Soc. 1870, p. 32G. 

 R. Amazons. 



4. Isthmiade macileyita^ n. sp. 

 I. ruhrce similis, at minor et multo angustior, thorace vix tubercu- 

 lato, etc. Yalde angustata, rufo-castanea ; antennis, elytris, pe- 

 dibus quatuor anticis, basique femorum posticorum pallidioribus ; 

 capite angusto nigro ; thorace elongato, angusto, medio paulo 

 dilatato, polito, supra sparsim punctate, tuberculo mediano dorsali 

 parvo ; elytris baud subito angustatis, apice late rotundatis, spar- 

 sim punctatis, nitidis. Long. 5^ lin. § . 



S. Brazil {coll. Dr. Baden). 



Differs from all other species by its narrow elongate thorax, 

 destitute of tubercles except the small discoidal one, the rest 

 of the surface being simply uneven, and sprinkled with small 

 circular punctures ; a lateral sulcus is very strongly marked 

 near the base. The antennse also differ in being distinctly 

 thickened towards the apex, with the joints compact and 

 moderately serrated. The elytra are subuliform, but not 

 suddenly narrowed, the lateral incurvature being much weaker 

 than in the other species. The wings also differ in not having 

 the yellow fascia which gives to the other species their strong 

 resemblance to the Braconidee ; they are very light brown, 

 and have only a faint indication of a yellow stigmoidal spot. 



Genus Ischasia. 

 Thomson, Syst. Ceramb. p. 163 ; Lacord. Genera, vol. viii. p. 508. 

 This genus is distinguished by its short and broad cunei- 



