644 Mr. Edward Saunders on 



Sphecodes subquadkatus, Sm. 



1901. Montserrat, near Railway Terminus : Jidy 15. 

 —1 $ E. B. P., 1 ? A. H. 

 Montserrat, near summit, San Geronimo (about 

 4000 ft.) : July 15.— 9 $ E. B. P., 3 $ 

 W. H., 6 ^ A. H. 



Sphecodes reticulatus, Thoms. 



1901. Montserrat, near summit, San Geronimo (about 

 4000 ft.) : July 15.— IG ^, 2 ? E. B. P., 22 ^, 

 1 ^ (one of the males being eaten by spider 

 on yellow umbelliferous flower-head), W. H.. 

 14^A.H. 

 Montserrat, near Railway Terminus : July 15. 

 —1 $ A. H. 



Sphecodes rufiventris, Pz. - - 



1901. Montserrat, near Railway Terminus : July 15. 

 —1 ^ A. H. 

 Montserrat, near summit, San Geronimo 

 (about 4000 ft) : July 15.-2 $ E. B. P., 

 1 ^ W. H. 



Ditto, sp. (?). 



1901. Montserrat, near Railway Terminus : July 15. 

 —1 $ A. H. 



[The five first-named species of Sphecodes are indis- 

 tinguishable in the field. They fly together, and were all 

 found visiting the flowers in the open grassy valley just 

 below San Geronimo, close to the summit of Montserrat, 

 on July 15, 1901. It will be seen that S.fuscvpennis and 

 S. rufiventris were much less common than the others. 

 The abundance of these Aculeates, as well as their inti- 

 mate association with one another and with their mimics, 

 is well shown in the following experience. I observed 

 resting on a flower in the valley a black fly with red abdo- 

 men, beautifully mimetic of these Hymenoptera. Mr. E. E. 

 Austen kindly informs me that the species is the Tachinid, 

 Ocyptera hrcvicornis, Lw. It occurred to me that by a 

 single strong sweep of the net I should probably secure 

 not only the mimic but a number of its models as well. 

 The twenty-one insects thus captured were carefully 

 labelled and kept distinct from others. With the excep- 

 tion of the fly all are Aculeates, and they are of course 



