GENERAL HISTORY OF BEES. 33 



and membranous substance. All these four joints are 

 either conterminal, or the two apical ones, or one of 

 them is articulated laterally, towards the apex of the 

 preceding joint. These two are always very short 

 joints, and are comparatively robust. 



The labial palpi are, in the majority of cases, about 

 half or two-thirds the length of the tongue, but in 

 Apathus and Apis they are of its full length. At the im- 

 mediate base of the tongue, and attached to it laterally, 

 rather than to the apex of the labium, are the paraglossce, 

 or lingual appendages, which are membranous and acute, 

 except in the Andrenidce., where, in some, their apex is 

 lacerated and fringed with short hairs. These organs 

 are always present in the Andrenidce and generally in 

 the Apidte, where they usually obtain extensive relative 

 development; but in the artisan bees they are all but 

 obsolete, and in Ceratina, Ccelioxys, Apathus, and Apis, 

 they are not even apparent. Their use also has hitherto 

 eluded discovery, but that they are not essential to the 

 honey-gathering instinct of the bee is especially proved 

 by the latter instance. 



The true tongue is attached to the centre of the apex 

 of the labium, having the paraglossse, when extant, and 

 the labial palpi at its sides. In the Andrenidce it is a 

 flat short organ of varying form, either lobatcd, emargi- 

 nate, acute, or lanceolate ; but in the Apidce, with Panur- 

 gus it immediately becomes very much elongated, and 

 with this genus the apparatus whereby the tongue folds 

 beneath obtains its immediate development; but this 

 development exhibits itself most fully in the genus An- 

 thophora. The tongue is usually linear, tapering slightly 

 to its extremity, and terminating in some genera with a 

 small knob. It is clothed throughout with a very delicate 



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