104 ENTOMOLOGICAL NEWS. [April, '03 



of the antennse hardly longer than the third, the species whose 

 females have the mandibles dentate are referred to the new 

 genus Stelidium, with .S. cressonii sp. nov. as the type, and 

 those with simple mandibles are referred to Machceris gn. 

 nov., type S. stygius having the vein rm present and the 

 clypeus convex, and Dialonia gn. nov., type 5. antennarics , 

 having that vein absent and the clypeus flat or a little con- 

 cave. 



In the paper on Andreninae, cited above, I have mentioned 

 thirteen species in which I have found the vein III5 wanting. 

 I neglected to mention the absence of vein r7n in one wing of 

 a single specimen of Trachandrena claytoniae. In the Spheco- 

 dinae, on the other hand, I have found the vein rm absent in 

 thirteen specimens of the following species : S. falcifer (i), 

 pimpinellcB (3), cressonii (2), stygius (2), anten7iaricB (5). 

 One of the last has the vein III^ wanting in one wing and is 

 the only example with that vein absent. 



Sphecodium cressonii is the insect I have identified as S. 

 mandibular is . Specimens sent to Mr. Cresson were deter- 

 mined as Sphecodes sp., from which it is evident that he did 

 not regard the species as .S. mandibularis. The structure of 

 the mandibles of that species is unknown. Machceris illinoen- 

 sis is based on a specimen with simple mandibles described as 

 a cotype of kS. pycnanthemi. The males of S. heraclei, pinipin- 

 ellce and antennaricB are here described for the first time. The 

 male of 6". arvensis, described as "entirely black, antennae 

 submonilif orm ' ' and 5. falcifer, described as ' ' entirely black' ' 

 are here characterized for the first time. 



►S. dichrous Sm. is probably based on the female of ►S'. arven- 

 sis Pttn. and the male of some other species, and 6*. confertus 

 Say may be the same as S. falcifer Pttn., but at present I pre- 

 fer to use Patton's names. 



In this paper cell Illg^second cubital cell ; vein rw^the 

 first transverse cubital nervure ; vein Ills^the second trans- 

 verse cubital nervure ; "joint" refers to antenna, "segment" 

 refers to abdomen; "enclosure" =the enclosed space on the 

 disc of metathorax. 



In my opinion these bees are inquilines of the Halictinae and 



