vni] SOME STRUCTURAL FEATURES 117 



to the end of the lor a corresponds to the labium, or 

 united second pair of maxillae, sometimes infelicitously 

 termed the "lower lip" of such an insect as a cock- 

 roach with whose anatomy perhaps some of our 

 readers are familiar. There is yet another pair of 

 important organs, viz. the (first) maxillae. The basal 

 joints of each of these is the cardo already mentioned : 

 to the lower flattened ends of the car dines and just 

 external to the articulations of the lora there is 

 fastened on each side a more or less rod-shaped piece, 

 the stipes. The stipites lie to right and left of the 

 mentum] and at their far end they carry flattened 

 blades whose inner faces are grooved so that they 

 sheathe, when closed, part of the mentnm and the 

 base of the tongue. These blades correspond, in my 

 opinion, to the galeae of lower insects, though some 

 authorities regard them as the laciniae. Springing 

 from the stipites at the same level as the blades, but 

 external to them, and projecting outwards, are the 

 jointed maxillary palps, right and left : the dimen- 

 sions of these vary greatly in the different genera of 

 bees. The intervals between the basal parts of the 

 whole of this complex apparatus are bridged over by 

 a membranous material which thus closes the back 

 of the head-recess, and forms round the upper ends 

 of all these mouth parts a kind of bag which leads 

 into the actual mouth. 



