An Essay on the Classification of the Parasitic Hymenoptera of Britain Which Correspond with the Ichneumones Minuti of Linnaeus
An essay on the classification of the parasitic Hymenoptera of Britain which correspond with the Ichneumones minuti of Linnaeus is a Victorian monograph of entomology published in the "Entomological Magazine" between 1833 and 1838, by the Irish entomologist Alexander Henry Haliday. The "Ichneumones minuti" of Linnaeus broadly correspond to the Braconidae and (superfamily Chalcidoidea). Haliday establishes higher level taxa (families) and describes new genera and species. The synoptic tables and descriptions are in Latin. Characters used are (mainly) morphology of the  abdomen and thorax, wing venation, number of antennal segments and number of maxillary palpi segments. The Essay begins with I "Tabula synoptica generum et subgenerum ichneumonum adscitorum Britanniae Synoptic Table of Genera and Subgenera of Ichneumons Found in Britain" (Braconidae). This functions as a dichotomous key. Part II is "Excerptae Quedam e Methodo Chalidum " Parts of a method and groups of chalcids The collections (other than his own) consulted were those of John Curtis and Mus. Soc. Ent. (Museum of the Entomological Society) Works consulted ("Auctores laudati") were "Of the Ichneumones of the Second Line, (Ichneumones adsciti, Essenbeck) "The authors  who have treated of the family at large are enumerated and noticed in detail by Professor Gravenhorst, in the Prolegomena to his History of European Ichneumones. It was not till the year 1811 that this supplemental branch was distinguished from the proper Ichneumones, by Doctor Nees von Essenbeck, whose system is more fully unfolded in the ninth volume of the New Series of Transactions, published by the Imperial Academy of the Physical Sciences, and has been followed by modern entomologists with few exceptions . That of Spinola, which Latreille adopted, and has adhered to in his latest works, differs in result  as detailed by them from that first mentioned, only as respects the genus Agathis, whose affinity to Bracones is admitted by Latreille himself. But, accurately examined, this method will be found to fail, as the variations of the palpi (on which it is founded) are much more extensive than those it comprehends. That of Von Essenbeck is therefore as superior in certainty as it is in facility of application; while the few Apterous species are, by habit, easily assigned to their proper station in the family. He has, however, employed the principle of Spinola for the distinctive characters of his  secondary groups, the Bracones and Bassi, a division which is accordingly defective in a similar degree. The difficulty of applying such a test appears from the fact that this most accurate observer has made glaring transpositions (I am acquainted with but two Aphidius ephippium and Alysia aptera) even among the genera strictly reducible to the lines of his own method. Professor Fallen, in a recent Essay, while he adopts the primary division of Von Essenbeck, has rejected these minor groups; but in reducing the number and extending the limits of the genera, has produced an arrangement which seems less simple  and natural. Of the genera, seven had been previously established (but not all equally well defined) by Fabricius,Latreille, Schrank and Jurine; the rest we owe to the labours of the same accomplished naturalist, who has besides described at length a considerable number of the European species; of which, also, several will be found dispersed among the Fabrician genera, and more collected and arranged in the Ligurian Fauna of Spinola. Seven species only are noticed by Linne; two of which are placed among his Ichneumones majores, four with the minuti, and one is appended to thegenus Cynips. The little that  is known of their instincts and economy is to be found in the pages of Reamur, and of the incomparable Swede, in patient observation almost his equal, and his systematic views (may I not say) unrivalled among his contemporaries. A few of the more familiar species have also been figured, and their habits noticed, by some of the older writers upon insects, as Madame Merian, Frisch etc.; and some interesting contributions to their history, in recent publications, are to be consulted under their respective heads"." List of Braconidae Described in An essay on the classification of the parasitic Hymenoptera of  Britain which correspond with the Ichneumones minuti of Linnaeus