OF WASHINGTON. 247 



finally stops at a given point and begins to gnaw the mem 

 brane until a perforation has been made. She then crawls 

 through this hole into the cell and deposits her eggs upon the 

 body of the larva, remaining inside and continuing oviposition 

 for several days. 



Another host-insect was added by Sir Sidney Saunders, who 

 exhibited before the Entomological Society of London in 1880 

 specimens of Melittobia reared from a briar inhabited by 

 Prosopis rubicola (See Trans. Entom. Soc. L,ond. 1880, Proc. p. 

 xvii) . 



With Packard's observations upon the species which he 

 found in this country parasitic in the cells of the leaf-cutter bee 

 (Megachile) we are all familiar. It is noteworthy, however, 

 that with the species which he described as Anthophorabia mega- 

 chilis 150 larvae were found clustering upon the outside of the 

 dead and dry bee larva, thus establishing primary parasitism 

 with this species. This extraordinary number of specimens upon 

 a single host larva is very remarkable in view of the observations 

 of Newport, Smith and Giraud. Packard also records a rear 

 ing from the cells of Ceratina. 



Mr. Ashmead's paper adds two entirely new hosts in Pelo- 

 preus and Chalybion, and, as I pointed out at the last meeting, 

 were it not for the earlier rearings of European workers, the 

 true host relations would be difficult to ascertain on account 

 of the heterogeneous nature of the contents of these mud- 

 dauber cells. Mr. Ashmead did not ascertain whether with 

 these wasp-cells the parasitism was primary or secondary. 



Mr. Ashmead also mentions Professor Riley's rearing of A. 

 megachilis from the cells of Anthophora in 1877, an( ^ it i s inter 

 esting to note that Professor Riley also reared a Monodonto- 

 merus from the cells of the same insect. 



A most interesting variation in the habits so far recorded has 

 been contained in Prof. Riley's unpublished notes bearing on 

 the life-history of Hornia and Anthophora for the last thirteen 

 years and has not before been published. It is here mentioned 

 with Dr. Riley's permission. On October 9, 1877, a number 

 of dipterous puparia were found in the cells of Anthophora 

 retusa. In April and May, 1878, a number of the adults 

 issued and proved to belong to the genus Syllegoptera, Pre 

 viously, however (Mar. 18), a number of Melittobia para 

 sites issued from the puparia and were mounted. 



This very remarkable variation in habit was not to remain 

 unique, however, for on September 25, 1891, Mr. A. N. 

 Caudell, of Indian Territory, sent in to the Division of Ento 

 mology specimens of the same species reared by Mr. Ash 

 mead from Pelopoeus, which he had also reared from a mud- 

 dauber's cell. He, however, had broken open the cell and had 



