THe HyMenoprera oF MINNESOTA 233 
this bee makes in a pithy stem or in solid wood. The genus is almost 
cosmopolitan, being found in nearly all parts of the world. It is 
about the size of a honey bee. Ashmead reported a Megachile nest 
(Psyche. Feb. 1894) with “thirty cells arranged in nine rows of un- 
equal length, the largest row contained. six cells. There must have 
%9 
been a thousand pieces of leaves used in the above. 
The genus Osmia is an in- 
teresting one; O. lignivora 
bores in maple, forming cells 
in its burrow. Ashmead, in 
reporting observations on this 
species (Psyche March 1894), 
states “the tunnel was over 
three inches long. Bless 
contained five cells.” O. lig- 
naria and O. pacifica build 
cells under stones, while the 
small O. simillima constructs 
cells in deserted oak galls.” 
It will be noted from the Fig. 124. Coelioxys octodentata Say, 
above that the diversity of in- Gua Te, 
stinct displayed in formation 
of nests of various species is quite remarkable. They generally 
choose hollow places already existing, excavations in wood, in the 
mortar of walls, in sand banks, and elsewhere. O. tridentata makes a 
burrow in the pith of bramble stems. 
The following are found in Minnesota either present in our col- 
lection, or on record as occurring here: Heteranthidium chip pewaense 
Graen., type-locality—Indian village at junction of the Lower Tama- 
rack and St. Croix rivers, Minnesota. Alcidamea sp., Andronicus sp., 
Coelioxys octodentata Say (see drawing), Heriades sp., Monumetha, 
Anthidium sp., Megachile (Xanthosarus) latimanus Say (col. pl. 3), 
Osmia (Ceratosmia) lignaria Say, Coelioxys sp. taken in Jackson Co. 
on sunflower and aster Sept. 12. 
CERATINIDAE 
Females and most males without a flat triangular area on apical dorsal abdominal 
segment; second recurrent vein never strongly bent or directed outward before join- 
ing first portion of subdiscoidal vein; tongue filiform; no depression or fovae on 
face; wings with three submarginal cells; apex of sixth abdominal segment in female 
