346 WASP STUDIES AFIELD 



was very light tan, almost white, thin and papery. The 

 second cell was three-fourths inch in length, unfilled and 

 likewise closed at the top with a wall of mud. Above this 

 was another cell only one-fourth inch in length, occupied 

 by A. capra. The next cell, one-half inch long, contained 

 a dead larva. The remaining four cells measured one-half 

 inch or less, and gave forth adult wasps or parasites. 



Ashmead 11 says, on the authority of Rev. T. W. Fyles, 

 that this wasp provisions its cells with larvae of the larch 

 saw-fly, Nemattis erichsonii, and is economically valuable, 

 destroying tineina, geometrina, tortricina, pryalina and noc- 

 tuina larvae in great numbers. 



Monobia quadridens Linn. [S. A. Rohwer]. 



The "carpenter mud wasp," Monobia quadridens, has 

 been widely known for years, but little has been noted on 

 its life history. That it is a mud wasp is true; that it is a 

 carpenter wasp is doubtful, since the authors who attribute 

 this habit to this wasp bring forward no positive evidence 

 except that the nests are found in wood-bores. This point 

 will bear further investigation, and until it is determined, 

 some more appropriate name should be applied to the in- 

 sect. The few known facts of its life history may be 

 summed up as in the following paragraphs. 



Ashmead 12 says that M. quadridens preys upon large 

 cut-worms which she carries to her cells. These cells are 

 made in the old burrows of the carpenter-bee, Xylocopa 

 virginica, by first renovating the sides of the old tunnel 

 with a thin veneering of clay and then dividing the space 

 into cells with clay partitions, working from the bottom 



11 Psyche 7 : 77. 1896. 



12 Psyche 7: 77. 1896. 



