Final answer:
The use of alliteration and tactile language creates sensuality in the stanza.
Step-by-step explanation:
Visually the use of alliteration is striking, particularly in the first line and almost equally so in the second. If you took the advice above about paying attention to the physical business of articulating the words too, you should be in a good position to discriminate between the rapidity of the flies and the heavier movement of the bees, and to notice how tactile the language is. The effect is actually to create sensuality in the stanza.