HARRY SCOTT SMITH. 115 



CO.^TRIBUTIOXS TOWARD A MONOGRAPH OF 



THE CERATINIO.E OF .^ORTH AND 



.niDDLF A. n ERICA. 



(Plate III) 

 BY HARRY SCOTT SMITH, LINCOLN, NEBRASKA. 



It was the ambition of the writer, when this study was first under- 

 taken about a year ago, to present at an early date a complete 

 monograph of the family Ceratinidse as represented in North and 

 Middle America. Consequently numerous letters were written to 

 different Hymenopterists and collectors throughout th'e country, 

 with the object in view of getting together a large amount of mate- 

 rial which would correctly represent the fauna of the territory which 

 was to be included by such a study. For the region north of Mexico, 

 in which the number of species is comparatively small, the results 

 were fairly satisfactory, but for the remainder of the territory, 

 Mexico and Central America, where the fauna is exceedingly rich 

 and varied, it seems next to impossible to get material at the present 

 time, owing to the scarcity of collectors in those localities. It is 

 hoped that this paper, preliminary as it must necessarily be, will be 

 effective in attracting the attention of collectors and others to these 

 most interesting and beautiful little bees, and that within the not far 

 distant future it will be possible to expand it into a complete and 

 representative monograph of the family. 



In all twenty-nine species are considered, of which nine are de 

 scribed as new, this number including all species known to have 

 been recorded from the above I'egion up to the present time. A 

 large per cent, of the species from Mexico and Central America are 

 known in one sex only, and this condition will of course exist until 

 numerous specimens are brouglit to light from those localities. The 

 greatest difficulty in the study of the genus is in the extreme simi- 

 larity of the females of certain species, of which the males are very 

 easily separated. In most cases, however, a close study of the punc- 

 turation and of the infuscation of the wings, together with the gen- 

 eral habitus, will serve to separate them, although the differences 

 are often hard to express in a table. Concerning the characters to 



TEANS. AM. ENT. SOC. XXXIII. (15*) APEIL, 1907. 



