On Braula caeca, Nitzsch, a Dipterous Parasite of the Honey Bee. 45 
that the newly-hatched Braula larva makes its way into a cell containing a 
bee larva, and feeds side by side with it on the food supplied by the nurse 
bees. Their minute size, white colouring and comparative scarcity in normal 
hives make their detection very difficult, and would account for their having 
remained unnoticed hitherto. 
The Pupa of Braula caeca. 
Six puparia were brought to light after a prolonged search in the hive 
mentioned above, and all of these were found in sealed cells containing 
Figs. 4-8. — 4. Antenna of adult. 5. Tarsus of adult. 6. Buccopharyngeal 
armature of larva. 7. a. Antenna of larva ; b. Sensory papilla of larva, 
anal segments ; c. Sensory papilla of larva, anterior segments. 8. Mouth- 
parts of adult. 
drone pupae. They were white, oval, about one and a-half millimetres in 
length, and attached to the sides of the cells. The puparium was found to 
consist of the last larval skin, not modified or thickened in any way, and the 
Braula pupa could be easily discerned inside. The peculiar sensory papillae 
(Fig. 7, b and c) and the moulted buccopharyngeal armature (Fig. 6) proved 
the identity of the puparia and the larvae described above. The adults had 
already emerged from four of the puparia when found, and these adults, pale 
yellowish white in colour, had made their way on to the drone pupae inside 
the cells. The remaining two puparia were kept in order to watch the 
emergence of the adults, but unfortunately both died soon after their 
