644 Mr. Edward Saunders on 
SPHECODES SUBQUADRATUS, Sm. 
1901. Montserrat, near Railway Terminus: July 15. 
—l ¢ E. BP. 1 2 ALL 
Montserrat, near summit, San Geronimo (about 
4000 ft.): July 15—9 f EL. BP. 3 ff 
WEL 36 6: Bs Ha: 
SPHECODES RETICULATUS, Thoms. 
1901. Montserrat, near summit, San Geronimo (about 
4000 ft.) : July 15.—16 ¢, 29 E. B. P., 22 2, 
1 2 (one of the males being eaten by spider 
on yellow umbelliferous flower-head), W. H., 
14 A.H. 
Montserrat, near Railway Terminus: July 15. 
1/4 -A, H. 
SPHECODES RUFIVENTRIS, Pz. 
1901. Montserrat, near Railway Terminus: July 15. 
—l1 7A. H. 
Montserrat, near summit, San Geronimo 
(about 4000 ft): July 15.—2 f E. B. P., 
ae WW 
Ditto, sp. (?). 
1901. Montserrat, near Railway Terminus: July 15. 
—19A.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. fuscipennis 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 brevicornis, 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 
