By the present extremely artificial plan the systematic sequence is disturbed; but the numbers, which will be found appended to the names in the table, will show their orderly succession. The natural generic character which precedes the account of each genus in the next division of the work will give the reason, by comparison, of the order in which “system” arranges them, and which being based mainly upon the differences of the trophi,—although, conjunctively with other characters, the trophi must necessarily be studied for its explanation,—their description in the description of the part of the imago is consequently referred to. Did we know exactly the uses of the component parts of the trophi severally, we should be better able to determine the legitimacy of applying them to the purpose of indicating the natural generic character, but being compelled, by reason of our ignorance of their several special functions, to avail ourselves of their form, relative proportions, and number only, uncertainty of having caught the clue of nature’s scheme must of necessity attend this distribution. But as what we do know of their uses in this family clearly indicates them to be an essential instrument indispensable to the economy of the insect, and which gives these organs an almost paramount importance, their comparative construction in the several genera would yield clear notions of the true order of succession, were we acquainted with the relative significancy of the various portions of the entire organ. Thus we see it numerically most complete in what we are pleased to suppose the least genuine bees—the _Andrenidæ_. In my series of the genera proposed in the preceding section, with the _Nudiped_ true bee _Melecta_ commences a deficiency of either some of the joints of the maxillary palpi, or of the paraglossæ;—throughout the artisan bees this abridgment is conspicuous both in number and proportion; and it culminates in what we consider the _facile princeps_, that most wonderfully organized of all insects—the genus _Apis_, which in its neuters has neither paraglossæ nor maxillary palpi, the latter being equally deficient in the male or drone, and in the queen; and in both the male and the queen the paraglossæ are but rudimentary. Nature appears too mysterious in her operations to permit us to solve these remarkable anomalies, for no combination of the genera founded exclusively upon them supplies us with Ariadne’s thread. Every such combination breaks up more harmonious groups, and we then retrace our steps, satisfied that we are on the wrong road.