103 



clayground in flat districts. It goes almost always to cactus 

 (Opuntia and Echinocactus). 



44. Ancyloscelis tricolor, Friese. Rarer than the precee- 

 ding and similarly a cactus insect. 



45. Ancyloscelis rufipes, Friese. Same as no. 39. 



46. Ancyloscelis nigriceps, Friese. As the preceeding. At 

 Chacras de Coria I found them in large numbers building 

 in colonies on the most sunshiny clay banks that were over- 

 grown with several low plants. 



47. Ancyloscelis clypearis, Friese. As the preceeding and 

 often taken together with it. 



48. Ancyloscelis facialis, Friese. Same as no 39. 

 Ancyloscelis nigerrima and A. tricolor are spring in- 



sects; the other Ancyloscelis species, especially rufipes and 

 nigripes are flying the whole summer through. 



49. Dipedia armata F. Sm. Not rare. I have found the 

 males in numbers sitting on dead branches close to a clay 

 wall, early in the morning. 



50. Anthophora saltensis Holmb. This bee is undoubtedly 

 a late summer one. In Chacras de Coria it chiefly visited 

 the previousiy mentioned Baccharis marginalis. 



51. Exomaiopsis Jensen!, Friese. Similar to no 11, but 

 only in few specimens. 



53. Schrottkya goeldiana, Friese. Has received a place 

 here by mistake. The species is not found in the Mendoza 

 region. 



54. Centris muralis, Burm. Burmeister in his original 

 description of this species in the „Stett. ent. Zeitschr. 1876" 

 gives also the following biological notice: „Das Thierchen lebt 

 in den aus gestampfter Erde aufgeführten Mauern der Land- 

 häuser und freistehenden Wänden, höhlt darin horizontale 

 Gänge aus und entwickelt in ihnen seine Brut. Es ist bei 

 Mendoza .... sehr gemein, in einzelnen Mauern zu Hun- 

 derten beieinander wohnend " Wonderfully correctly 



expressed in few words ! 



This extraordinary, large species is an especial spring 

 insect. Anyone Coming to Mendoza, or the smallest towns 

 in the neighbourhood, in October or November could not 

 help noticing this stately, white woolly bee flying in large 

 numbers and with the swiftest and loudly humming flight, 

 backwards and forwards along the walls, where they build; 

 anyone, who did not know ihese insects, would suppose that 

 they were strongly teased and engaged in a prolonged battle. 

 The species is hardly to be met with after the above men- 

 tioned months. 



