[BCHFTBOTl :. 



feet, : 1 1 1 « 1 when the sand accumulated way 



it \\<>ul<l retreat backwards and push the dirt .-till farther 

 back from the moutl cell with its hind legs. In this 



way. working literally with tooth and nail, it dug a shaft 

 five or >i\ inches deep, and then flew away ; 

 hop] »re it. finally filling the mouth so that no dis- 



tinct tn its work would remain. 



A decided step upward is the horn 

 the mud-dauber. This • moisti 



the dirt with its saliva, forming pel 

 of mud, which it plasters on wall.-? or 

 rafters, storing the cell with spidi 

 etc. In our common yellow- a I mud- 

 daubei (/' s fluvipes) the cella are 



built of long pellet- of mud placed in 

 and diverging from the mid- , 



Fig. -a An African 

 die. inn 



The u l-wasps excavate their burrows in the hollow 



sterna of pithy plants, such as the i spberry, 



or blackberry, the idea seeming to be much labor 



as possible; some spi ies going so far ir rather doii 

 little, as to relit old nail-holes for their nesting pui 



Coming to the true solitary wasps, we find 

 very different nest-building habits. While one kind of 

 Odynerus builds separate cells of mud, placing them in 

 oak-galls or in 3 of the tent-caterpillar, another 



bail) ral cell her under a common coverii 



sandy mud fastened to a stack of grass. M ire <>f an archi- 

 ural effort is seen in the flask-shaped 1 mad which 



'.'in t builds, attaching several of them in a 



row to a branch, filling the interiors with lit; 



a more advanced order is tl which 



shows that each cell is built independently in n 

 agons; sometimes the cells are arranged in two or three 

 rows; while in the nest of our ten to 



be found attached to bushes, the cells arc ther 



in one plane or story, lint in a deli< a S >nth 



