198 
Psyche 
[June 
These nests are constructed very similarly to those of the famous 
European mason bees of the genus Chalicodoma , and I propose that 
we also use the vernacular name “mason bee” to refer to H. antho- 
copoides and related Hoplitis ( Hoplitis ) with similar habits. My 
study of its nesting behavior in New York will be presented in a 
future paper. 
None of the native American Ploplitis whose biologies have been 
investigated are mason bees. All but one species build rows of 
cells, one above the other, in tubular holes in dead stems or tree 
trunks (reviewed by Michener, 1947, and Hurd and Michener, 
I955)* The one exception, H. ( Dasyosmia ) biscutellae (Cockerell), 
has been recorded as nesting in soil by Linsley and MacSwain ( 1943) 
and reusing mud-dauber ( Sceliphron ) nests by Stephen, Bohart, and 
Torchio (1969)- However, some American Osmia build exposed 
nests on rock surfaces (Stephen, Bohart, and Torchio, 1969), 
including at least one species at Rensselaerville. 
Freshly emerged males and females of H. anthocopoides were 
first seen on June 14. Adults are common to the latter part of July, 
when they taper off, and are rare after August 1. The last adult 
was seen on August 19. 
Discussion 
Megachilid bees have frequently been transported long distances 
by man, probably because their nests are often concealed in the 
stems and crevices of plants and other articles of commerce. In the 
United States, 5 Old World species other than the mason bee have 
been intruduced in historical times (Mitchell, 1962; Jaycox, 1967). 
Megachile rotundata (Fabricius) and M. concinna Smith are now 
both widespread in this country, and the former species has been 
semi-domesticated for alfalfa seed production in the Pacific North- 
west. Megachile concinna presumably reached this country from the 
West Indies after World War II, and had probably reached the 
West Indies from Africa in the early 19th century. Megachile 
apicalis Spinola has been recorded several times from eastern North 
America but may not be established. Chalicodoma lanata (Fabricius) 
was apparently introduced into the West Indies with the slave 
trade, and has recently been found in southern Florida. The most 
recent introduction has taken place around Ithaca, New York, 
about 120 miles from the range of H. anthocopoides, where the 
European Anthidium manicatum (Linnaeus) was first collected in 
1963 (Jaycox, 1967). This species is common in the Ithaca area and 
