[[p. 519]] The following Catalogue is founded mainly upon the specimens collected by myself, with the addition of those found by Mr. Lamb at and near Penang; and I have incorporated all those contained in the Collections of the British Museum and of Major Parry, and have further introduced the names of all the described species of which I have not seen specimens, so as to form as nearly complete a local catalogue as can be done without studying the Continental Collections. In Gory and Percheron's "Monographie des Cétoines," published in 1833, only 45 species were described from the Malayan Islands, and a large portion of these were from the single island of Java. Burmeister's "Handbuch der Entomologie," dated 1842, has 60 species from the same region. The British Museum "List of Cetoniadæ," in 1847, gives 74 species as known, but several of these were undescribed. Lacordaire, in his "Genera des Coléoptères," in 1856, gives a list of 85 described species as found in this district. Since then Thomson has described 9, all collected by myself; Vollenhoven has added 14, obtained from Dutch collectors, and other authors 5; and in this paper are described 68 additional species, (also two from Cambodia),¹ bringing up the total to 181 Malayan Cetoniidæ, not including the Trichiidæ.

     Taken as a whole the Cetoniidæ are decidedly scarce in the equatorial regions. Now and then a species will occur in profusion, but this is an exception; the rule being that single specimens of a very few species are to be found at any one time. There are few groups in which mere collecting will do so little towards obtaining a fair proportion of the species. Fine weather, and good luck in being in the right place at the right time, will help the travelling collector to a few good things; but to obtain any thing like a complete knowledge of the group requires a long residence and the assistance of the whole native population. This is well shown by the comparatively small number of species collected by [[p. 520]] myself. During eight years most assiduous search, in about thirty different localities, I only obtained 85 species, or considerably less than half the number now known. Compare this with other families. I collected about a thousand species of Longicorns, and I feel certain that the additional species from the Malayan region either described or existing in English collections could not exceed four hundred. So in the Buprestidæ, the 355 species collected by me must form a very large proportion of all that are known from the region, for Lacordaire's work does not indicate more than 50 species from the same countries. In the Papilionidæ, out of 123 known species I collected myself no less than 92; and of Pieridæ 121 out of a total of 169.

     The Cetoniæ of the Malayan islands are neither so large, so varied, nor so numerous as those of the continent of Asia. The fine horned Goliathinæ of the Himalayas are represented only by two species of Mycteristes and a few small Heterorhinæ, and there is nothing to make up for this deficiency. Lomaptera, Chalcothea, and Macronota, are the most characteristic Malayan genera, and contain many beautiful species, but none exceed the middle size. The number of species found in any one locality seems to be influenced, first, by proximity to the continent, and next, by the mass of the island. The Peninsula of Malacca, though but very partially explored, has 44 species; Java, the best known by far of all the Eastern Islands, has 46; but some of these are book species which may have been already included under other names, and even if they were all distinct, the number is really less in proportion than that of Malacca, when we consider that the whole surface of Java is more or less known, and that the whole island has been for more than a century in the possession of Europeans, while in the Malay Peninsula small collections have been made only in a very few limited localities. Further from the continent, we find the whole group of the Philippines with 32 species; further still, Celebes with 19; Ceram and Amboyna with 11; the Aru Islands with 9, and the great Island of New Guinea with 12,--the slightly increased number being due to its large area, and very many more species remaining to be discovered there. The same diminution in receding from the continent is visible if we divide the Indian from the Australian regions of the Archipelago, the [[p. 521]] former (extending as far east as Java, Borneo, and the Philippines) having 114 species, while the latter (stretching from Celebes to the Solomon Islands) has but 70.

     This group of insects furnishes us with a very satisfactory confirmation of the view that the division of the Archipelago just alluded to is a truly natural one, however much it may be occasionally masked by special circumstances. No less than nine genera, Mycteristes, Agestrata, Clerota, Plectrone, Chalcothea, Centrognathus, Rhagopteryx, Macroma, and Euremina, are strictly limited to the Indian region; and two more, Heterorhina and Clinteria, only pass beyond it into the closely connected chain of islands from Java to Timor, and in the case of a single species into Celebes. Three genera, on the other hand, Schizorhina, Anacamptorhina, and Sternoplus, are restricted to the Australian region, and the genus Lomaptera is almost so, only 3 species out of 25 passing beyond its limits, of which one, L. striata, is the most aberrant of the genus, and the other two are closely allied forms which have a wide range on the continent. These remarkable limitations of genera do not accord with the supposition that the whole Archipelago forms a single zoological region, but they strikingly support the view that there is a line of very ancient division between its eastern and western halves, while the divisions between islands and groups of islands within either half are of more recent establishment, and are therefore less efficacious in limiting the range of species or of genera.

     In classification I have not attempted to do more than follow Lacordaire, and do not profess to criticize his work in this very difficult family. I have proposed two new genera for species that appear to me strikingly distinct, and I have indicated two others that will probably have to be established when more materials are obtained.

     The phenomena of variation are well exhibited here, and there are many cases in which structural characters are not a surer guide to specific distinction than colour or markings. In Lomaptera pulla and Macronota regia we have insects of wide range, and with such an amount of variation, that few would consider it possible that the extremes, considered alone, could be the same species; but these extremes are united by a series of intermediate forms, many of which occur together in the same locality. In other cases we have allied forms from adjacent islands [[p. 522]] which so nearly resemble each other that it seems impossible to separate them, but close examination reveals minute but important differential characters which seem quite constant. Such are Macronota carbonaria and M. egregia, var. nigra; Schizorhina Whitei and S. bouruensis; Lomaptera arouensis, L. ceramensis, and L. cambodiensis; Lomaptera pygidialis and L. batchiana, and some others. Such cases force us to the conclusion that structural and superficial characters are about on a par as regards introducing any certainty into the definition of a species, and that a decided difference of colour and marking is often a better character than a slight modification of the form or sculpture of some important organ. Both are sometimes very constant, both are at times liable to much variation, and it is a matter of judgment and opinion how far we are to be guided by either in any particular case.

     It will be as well, to avoid misapprehension, to say a few words about the localities given for the various species. All the specimens noted as from my collection were either obtained directly by myself in the localities named, or through collectors whom I knew well. All these localities therefore may be relied upon as perfectly authentic. The specimens collected by Mr. Lamb, and noted as from "Penang," were most of them collected, not in the island, but in the main land of the Malay Peninsula opposite, termed the "Province of Wellesley." "Penang" may therefore be held to signify merely a particular sub-district of the Malay Peninsula. The collections presented to the British Museum by Mr. Bowring comprise several thousand specimens labelled "Java." These were not collected by Mr. Bowring himself, but formed part of an extensive collection purchased by him, and said to have been collected in "Java and the adjacent islands,"--but chiefly in Java. It is to be remembered also, that for the last hundred years, collections have arrived in Europe from Java, which did not necessarily consist only of Javanese insects,--sometimes, on the contrary, they have been entirely formed in other islands. It follows that my own collections and those of Dr. Horsfield are the only perfectly authentic materials for the Entomology of Java, although I fully believe that by far the larger part of the species imputed to that island do really inhabit it, since it is unusually rich in every department of Zoology. The specimens from the [[p. 523]] Philippine Islands are no doubt mostly well determined. A large number were collected by the late Hugh Cuming, and as there is scarcely any direct communication between this part of the Archipelago and any other, the collections are not likely to have been misappropriated. I have prefixed to each genus a few words on its distribution, and on any particulars of its habits known to me; and have added tables exhibiting at one view the distribution of the species, genera, and sub-families, through the various islands, groups of islands, and regions of the Archipelago.

Note Appearing in the Original Work

1. The whole of the new species were characterized in Proc. Ent. Soc. 1867, pp. xcii-xcvii, published in July, 1867. --Sec. Ent. Soc. [[on p. 519]]