218 bulletin: museum of comparative zoology. 



RiBAUTiA Brolemann. 

 Arch. zool. exp. et gen., 1909, ser. 5, 3, p. 335. 



RiBAUTiA BOUViERi Brolemann. 



Bull. Mus. hist, nat., 1909, p. 7, fig. 19-26. 



Locality. — State of Amazonas : Brazilian Guiana, on the upper 

 Carsevenne or Cal^oene (Geay, collector). 



Taiyuna Chamberlin. 



Pomona college jour, ent., 1912, 4, p. 661. 



This genus was previously known only from California and Arizona 

 in which states three species are known to occur. 



Taiyuna australis, sp. nov. 



Color yellow, of weak orange tinge cephalad. Head and prehensors 

 darker, brown. Antennae similar to head, but paler distad. 



Body attenuated cephalad, more strongly so caudad; moderately 

 robust. 



Head widest a little caudad of level of labrum from where the sides 

 converge a little and are straight to the rounded posterior corners and 

 also converge slightly cephalad to the similarly rounded anterior 

 corners; posterior margin widely, somewhat flatly, convex; anterior 

 margin with each side straight, extending from corner a little cephalad 

 of mesad to the middle where there is a distinct notch. In type the 

 head is 1.38+ times longer than wide. 



Inner branch of first maxilla terminating in an auriculiform mem- 

 branous lobe at distoectal corner; bearing 3 to 5 bristles. Distal 

 joint of outer branch long, apically rounded with the dorsoectal edge 

 strongly chitinized; bearing about six bristles; membranous lappets 

 long and spinulose, the distal one larger than the proximal, and ex- 

 tending much beyond distal end of the outer branch. 



Coxae of second maxillae united at middle merely by a narrow mem- 

 branous bridge; more strongly chitinized along edge below disto- 

 mesal angle at which there is no trace of a process. Pleurosternal 



