Since Fabricius' time the terms proboscis and haustellum have been used somewhat 

 indefinitely. Gerstfeldt sought to explain (p. 13 of his dissertation") Fabricius' 

 meaning, but seems to have failed in clearly comprehending the difference which 

 the latter intended to establish between proboscis and haustellum. In the course 

 of this paper proboscis will be used, in its generally accepted meaning at present, 

 as a designation for such of the mouth-parts of diptera, taken together, as form 

 their more or less flexible, shorter or longer, sucking apparatus. 



According to J. V. Cams (Geschichte der Zoologie, p. 559) Fabricius also 

 divided the insects into sucking and chewing species, a classification followed later 

 by Clairville, 4 Lamarck, Gravenhorst, and many others. 



SAvifiNY, 5 in 1816, took the next important step in advancing our knowledge 

 of the mouth-parts of insects, and showed that all the mouth-parts of insects 

 were reducible to the same plan, that is to the plan which they present in 

 chewing insects. Most of Savigny's work was done on lepidoptera, because the 

 lepidoptera were supposed to have mouth-parts farthest removed in structure from 

 those of chewing insects. Savigny says (p. 10-J1), "I am convinced that, when 

 one shall have better examined the mouth of the insects properly speaking, that 

 is to say those with six feet and two antennae, one will find that, whatever 

 form it may assume, it is always essentially composed of the same elements." . . . 

 " One discovers that the organ is the same ; the use alone is modified or 

 changed. See the constant plan of nature. Thus I think I can assert, from 

 this time on, that the mouth of the diptera is formed of the same parts as that 

 of the hymenoptera. But to prove this proposition it is necessary to commence 

 by explaining the organization of the mouth of the hymenoptera." * Savigny 

 says further (p. 13-14), "The mouth of the hymenoptera is, then, composed of four 

 unpaired organs, without including the jaw or mentimi; namely, the upper lip, 

 the epipharynx, the hypopharynx and the under lip ; and of two pairs of organs, 

 the mandibles and the maxillae. The same organs are all found, either separately 

 or simultaneously in the mouth of the diptera. The under lip exists almost 

 always; it constitutes the proboscis, properly speaking. The maxillae exist 

 likewise almost always; it is these organs which bear the palpi, so that the 



* '-Je suis convaincu que, lorsqu'on aura mieux examine la bouche des insectes propre- 

 ment dits, c'est-a-dire, asixpattes et a deux antennes, on trouvera que, quelque forme qu'elle 

 affecte. elle esttoujours essentiellement composee des memes elements." .... "On sait que 

 1'organe est le nieme: 1'usage seul est modifie ou change. Voila le plan constant de la 

 nature. Ainsi je crois pouvoir assurer des a present que la bouche des Dipteres est formee 

 des memes parties que celle des Hymenopteres. Mais pour demontrer cette proposition, il 

 faudrait commencer par exposer I'organisation de la bouche des Hymenopteres." 



1* 



