1922 ] Taylor — Biology of Wasps of Genus Ancistrocerus 
63 
2. The nests made by these wasps in glass tubes have the 
following characteristics : 
a. Tubes having diameters of from six to eight millimeters 
were utilized by the wasps. 
b. Nests consist of from one to four cells, these apparently 
varying in length conversely to the diameter of the tube, the 
inner cells being usually larger than the outer. The cells are 
separated by partitions of mud which the wasp makes by mixing 
fine sand and water. 
c. The cells are each provided with an egg, suspended by 
a filament from above and each contains from three to fourteen 
caterpillars; these are supplied after the egg has been deposited. 
3. The caterpillars are paralyzed by the wasp by stinging 
probably at some point near the thorax. 
4. From rather fragmentary evidence it appears that the 
larger, inner cells contain eggs which are destined to produce 
females, while the smaller, outer cells contain those which are to 
become males. 
5. There are probably two generations of these wasps 
annually, the eggs of the first being laid from mid to late June, 
the adults from them appearing during the first half of July. The 
eggs of the second generation are laid during the latter part of 
July and the first of August, the wasps from them hibernating as 
larvae and probably emerging in June. 
6. From the longevity of certain of these wasps in captivity 
it is concluded that the females live long enough to construct 
several nests of the sort described here. 
7. The females are apparently guided to their nests by 
certain landmarks, but are not helpless when such landmarks are 
removed or distrubed. 
8. Dipterous larvae, Chrysiclidae and perhaps ants have 
been observed as enemies of the species studied. 
