OCR Text |
Show 1887.] OF THE SUBFAMILY LANGURIIDES. 359 close affinity with Cerglon, but simply was doubtful whether, with Latreille, their proper place was with the Erytolidte, or whether it should be with Eumorphus. The opinion which has been put forward that they might be very much modified Phytophaga is negatived by the fact that the tarsi are five-jointed, the small fourth joint, which is like a nodule at the base of the claw-joint, being closely analogous to the similar joint in both the Erotylidae and Endomychidse, though the alliance is greater with the former than the latter family, in which there are but four joints inclusive, while in both Erotylidse and Langurise there are live. I shall now give a summary of the characters to which I have paid especial attention, and upon which this attempt at classification of these Beetles is founded. 1. The Head.-The antennse are eleven-jointed without exception ; the two basal joints are short and stout, not very different in length, the third rather longer than these or succeeding joints ; the four apical joints are pubescent, those preceding them either glabrous (the more evoluted form as in Pachylanguria) or clothed with hairs. The ocular striola is a groove above the canthus or rim of the eye and is of great use ; it is absent in certain genera, very distinct in others, and modified in degree of fineness or in length; in others, from it in front starts a sharp ridge, forming the upper edge of the socket of the antennae and bordering the epistome. This latter is the part of the head immediately before the labrum, and both afford some useful characters. On the occiput are frequently found very minute raised ridges, or carinae, and these are the organ of stridulation. Sometimes they are so obsolete that the greatest pains is necessary to trace their rudiments, or more correctly their nascent origins. I do not consider them of importance for classification, nor even as truly generic characters. The eyes themselves are either coarsely or quite finely granulated (i. e. the facets are like a cluster of ocelli, or are much modified so as to approach the more highly evoluted eyes with even surfaces). These give generic characters, but, as in the Cleridae, do not serve for higher aggregates. The palpi, maxillae, labium, or mentum are not variable to any great extent. The labrum varies in degree of length, but I have not been able to use the trophi. 2. The Thorax.-The pronotum is variable in shape, but does not afford generic characters ; the presence of basal sulci indicates affinity with both Erotylidae and Endomychidse, but is also with many of the characters common in a less degree in the Phytophaga. The prosternum and mesosternum bear a singular resemblance to those of the two first-named families, and, as in them, afford good and constant generic characters ; the reflexed edge of the pronotum has no lines nor plication (such as is found in certain Malacoderms), and I do not find any characters of more than specific value there. The metasternum with its episterna and epimera will no doubt ultimately prove as valuable as the prosternum; I regret that I cannot work out the characters of this part, mainly because it cannot be done properly without spoiling the specimens by dissection. |