16 Trans. Acad, of St. Louis 



Their thin walls would certainly offer little protection 

 from the elements. The five mentioned above all fell 

 when I tried ever so gently to move the twig to photo- 

 graph them. This cluster also suggests that one mother 

 may be capable of building that number, although of 

 course we have not absolute proof that they are the work 

 of one parent. These facts, as well as the fact that these 

 wasps have been seen late in the autumn, lead me to 

 suspect that these wasps hibernate as adults. 



Monobia quadridens. This wasp was bringing in cater- 

 pillars at intervals of thirty minutes, at 6 a. m. on June 

 28. Five days later the nest was examined; the cater- 

 pillars were still alive, although much shrunken. They 

 were very dissimilar, and represented probably two 

 species of the Gelechidae. This wasp uses the old gal- 

 leries of carpenter bees and one such nest with mud par- 

 titions is shown in PI. VII, fig 10 ; all three young were 

 parasitized by cuckoo bees. The first of these to emerge 

 was the lowermost one, the first e^g deposited. This 

 made a hole in its cocoon and a neat hole in the mud plug 

 above, entered the cell above, crept past its younger 

 brother and bit a neat round hole in the second plug also. 

 It was in the antechamber when I discovered and re- 

 moved it. 



Ancistrocerus near tigris Sauss. [S. A. Rohwer]. This 

 was seen to enter and leave an old beetle burrow in a 

 fence-post. The hole contained no nest ; the purpose of 

 the visit was not ascertained. In earlier studies we have 

 learned that this species inhabits the old nests of mud- 

 daubers, Sceliphron caementarium. Five of these wasps 

 emerged from sumac stems taken in St. Louis, between 

 April 3 and 7, 1919. 



Stenodynerus quudrisectus Say. [S. A. Rohwer]. This 

 was captured on the window of a log chicken-house, Sep- 

 tember 12, 1917. 



Stenodynerus zendaloides Robt. [S. A. Rohwer]. This 

 wasp hatched early in May, 1918 from a sumac twig 



