CLASSIFICATION OF THE BEES. 69 



18. Submedian cell distinctly longer than the median ; maxillary palpi 6-jointed. 



Nomada Scopoli. 

 Submedian cell not longer than the median ; maxillary palpi 5-jointed. 



Brach} uomatfa Holmberg. 



Family VII. CERATLNIDjE. 



(The Small Carpenter Bees). 



The bees placed in this family I have called "The Small Carpen- 

 ter Bees," on account of their habits being similar to the large car- 

 penter bees, or the family Xylocopidse. Indeed, their relationship 

 to this family is extremely close, although I consider them just as 

 closely allied to certain Ostniines in the family Megachilkhe. 



The European authority, Dr. Schmiedeknecht, has placed them 

 in the family Xylocopidse and this arrangement has been followed 

 by Dr. Friese and others. 



They are mostly small metallic blue, blue-black (rarely black), 

 blue-green, or bright green bees, almost entirely devoid of pubes- 

 cence and without a distinct polleniferous scopa on hind legs and 

 venter, and in their very much smaller size and general appearance 

 are so totally different from the large carpenter bees that I cannot 

 believe they are at all related. I have therefore not hesitated, since 

 the characters lacking in the species are of great taxonomic import- 

 ance, to separate them as a distinct family. 



Two genera can be distinguished, as follows : 



Table of Genera 



Third cubital cell, along the cubitus, fully as long as the first, but so much nar- 

 rowed ahove, along the radius, that its length is reduced one-half; 

 second cubital cell the shortest, narrowed above; second and third 

 cubital cells each receiving a recurrent nervure beyond the middle; 

 antenna; short, subclavate; head seen from in front a little longer 

 than wide; maxillary palpi 4-6 -join ted ; labial palpi 4-jointed. 



Males ; mandibles bidentate 2. 



Females; mandibles tridentate. 

 Maxillary palpi 4-jointed' 



Zatlontomerus Ashm. n. g. (Type C. tejonensis Cr.)- 



Maxillary palpi 6-jointed Ceratina Latreille. 



2. Hind femora produced into a large triangular tooth beneath: genital ventral 

 plate trapezoidal, not wider than long; maxillary palpi 4-jointed. 



Zadonl « ru- Ashm 



Hind femora normal; genital ventral plate semicircular, twice wider than 

 long; maxillary palpi 6-jointed Ceratina Latreille. 



TRANS. AM. ENT. SOC. XXVI. JUNE, 1899. 



