1922] Taylor — Biology of Wasps of Genus Ancistrocerus 65 



1905 Wasps, social and solitary. Cam- 

 bridge, Houghton-Mifflin. 



1918 Rau, Phil and Nellie. Wasp studies afield. Princeton, 

 Princeton Univ. Press. 



1916 Roubaud, E. Recherches biologiques sur les guepes 

 solitaires et sociales d'Afrique. La genese de la vie sociale 

 et revolution de I'instinct maternel chez les Vespides. 

 Ann. Sci. Nat. (9) Zool. 1916, pp. 1-160. 



1892a Verhoeff, C. Neue und wenige bekannte Gesetze aus der 

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1892b Beitrage zur Biologie der Hymenop- 



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Explanation of Plate IV. 



Fig. 1. Longitudinal section of nesting block, showing 

 glass tube in position and nest no. 2 containing four cells, each 

 with its egg and caterpillars. (% natural size.) 



Fig. 2. Nest built by Ancistrocerus sp. showing three cells 

 with larvse in cocoons. (% natural size.) 



Fig. 3. Egg of Ancistrocerus sp. with suspending filament. 

 (This and the next two figures enlarged about fifteen times). 



Fig. 4. Same egg as in figure 3, about to hatch. 



Fig. 5. Larva (just hatched from egg shown in figure 3) 

 suspended from the shrunken chorion. 



