NO. 14 SENSE ORGANS ON MOUTH-PARTS OF BEE McINDOO 



31 



{Hyp) were taken from another section in which the hypodermal cells 

 were better fixed. Any section through the middle of a mandible 

 invariably shows from two to four large pores, from one to three 

 small pores, and one or more innervated hairs. The nearer the distal 

 end of the mandible a section is taken, the fewer the large pores and 



Fig. 6. — Internal anatomy of mandible of a worker honey bee, showing how 

 well this appendage is innervated. A, semidiagram of cross-section through 

 middle of mandible, showing innervation of olfactory pores (Por) and tactile 

 hairs (ci), blood sinuses (BISin), nerve (N), nerve branches (NB), tracheae 

 (Tr), etc. The details of the hypodermis (Hyp) were taken from another 

 section, x 185. B, diagram of transverse-longitudinal view of mandible, 

 showing innervation of olfactory pores (Por) and tactile hairs (bi, bi and c-,), 

 and superficial appearances of these sense organs. The hairs in solid black are 

 not innervated, while all the others are connected with sense cells (SC). See 

 page 54 for other abbreviations. 



the greater the number of small pores and innervated hairs it shows. 

 Large hypodermal cells, called hair-mother cells (HrMC), are often 

 seen beneath the largest hairs on the mandibles. They send processes 



