11 



Thorax : — Dark bronze in color, elothed with short yellow hairs ; 

 sentelliim short and broad, abovit foiir times as broad as loricr, the hind 

 niargin straight and parallel with fj'ont margin, a spine at each poste- 

 rior córner of sentelhnn. 



Legs: ■ — Black with brownisli pile. 



Abdomen -. — Bronzy black witli short ])rown pile and slighth^ 

 longer and yellowish pile at anterior eorners and along the sldes of the 

 tergites; a flattened tnft of black hair projecting from above the first 

 spiracle. 



Wing : — Hyaline, biit with the veins rather strongly and broadly 

 infu,scated; stigmati,qal crossvein present ; spnrions vein actually 

 joining the fourth vein ; apical crossvein strongly sinnons, the apical 

 portion recurrent and with a spnr at its base. 



A male Microdon was seen on the same rock where the females 

 were eaptnred bnt could not be procured. Presiimably it ií* the male 

 of the species here deseribed. It was smaller in size and the abdomen 

 was of a distinct brown color. 



Two females. 



Tijpe ¡oc.aUty. — Alta Gracia, Córdoba (20 January, 1927, R. C. 

 Shannon). 



It is very appropriate to ñame this species for Doctor Carlos 

 Bruch, who has so greatly advanced onr knowledge on the ants and 

 myrmecophiles, as well as the Coleóptera, of Argentina. 



Subfamily Ceriodinae. 



Two species of the subfamily Ceriodinae representing two genera 

 are at hand. The antennifer (antennal proeess) is very short in both, 

 iikewise the abdomen has a basal eonstriction. 



Cerioides : — Metasternum membranons on posterior snrface. 



Palijhiomyia: — Metasternum completely girdled with chitin. 



Genns Cerioides Rondani 

 Cerioides harhipes Loew 



This species is very similar to a species of wasp, Moniezumia sp. 

 which occnrs in the same región. Also, there is a species of Ceramby- 

 oidae, Sphecomorpha niurina Khig (which has very small elytra, bnt 

 large membranons wings), and a species of Lepidoptera, Pseudosphe.r 

 novercida Kaye, Syntomidae), which also bears a very cióse resem- 

 blance to the same species of Montezumia. (Determinations- made by 

 Doctor C. Bruch). The appearance of the fly, moth and l)eetle is so 

 wasp-like that the collector hesitates to pick them up with his fingers 

 until a cióse inspection proves them harmless. 



Male: — A rather large black species (14.0 mm. ; wing 11 mm.), 

 the wing heavily infuscated liasally and anteriorly. 



Head: — Triangular in oulline from the frontal aspcct, due to 

 the face being strongly produced downwards; occiput covered with 

 whitish pruinosity; ocellar triangle black, equal-sided ; frontal triangle 

 sliort but very broad, a short antennifer arising therefrom and suppor- 



