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Show 634 SIR G. F. H A M P S O N O N T H E [June 1, is typical of the group. This diversity is usually correlated with the development of various other secondary sexual characters, one of the most common and remarkable being an ear-shaped tympanic vesicle at the base of the costa of fore wing covered by a drum of fine corrugated membrane. A carefully elaborated classification of most of the genera was published by the late E. M . Eagonot in the ' Annales de la Societe Entomologique de France'l; but a large number of the species were unknown to him, and his material was insufficient for him to discover the large amount of sexual dimorphism that exists. He defined the Chrysauglnce as differing from the Endotrichince in being stoutly-built insects, and includes in the latter subfamily many of the genera which by m y definition fall into the former : the paper, however, formed a most important contribution towards a correct classification of the group, which was originally defined and systematized by Lederer in 1863. None of the genera are of a very generalized structure, but Chrysauge itself, apart from its secondary sexual characters, is regarded as the least specialized, with its short porrect palpi and median nervules of both wings arising from the cell in its 1st section. From it were developed a group of genera with downcurved palpi, of which forms like Anemosa and Pelasgis have very long palpi; Semnla with the palpi smooth and a tuft of hair on the antennas; Ullosoma and Acutla with one of the median nervules absent in one or both wings ; Condylolomla with veins 2 and 3 of the fore wing stalked ; Itambe and Microzancla with extremely falcate fore wings; Macna with very long straight palpi in female, upturned and angled with hair in front in male ; Psectrodes and Acrodegmia with very long palpi ending in a large rounded tuft of hair on 3rd joint. Another large group of genera have the palpi upturned, of which the majority have short palpi, such as Sthenohcea with vein 4 of hind wing absent; Dasycnemla with veins 4, 5 of both wings stalked ; Anlsothrlx without a frontal tuft; Rucuma with tufts of hair on frons, mid tibias, and tarsal joints, and excisions in the costa of fore wing ; whilst a few genera have very long upturned palpi, culminating in Tamyra with a rounded brush on 3rd joint. A very curious structure found in several of the genera, of which Casuaria is typical, is the development of the retinaculum into a complete ring, the frenulum being thickened, flattened, contorted at base and with a short lower fork; this form being associated with a glandular swelling and tufts of hair on underside of costa of fore wing and the tympanic vesicle on upperside mentioned above. Subfamily CHRYSAUGINEE. Froboscis well-developed ; palpi of extremely different forms in the different genera ; maxillary palpi absent; frons usually with a tuft of hair. Fore wing with vein 7 stalked with 8, 9 in female; 1 Ann. Soc. Ent. Fr. 1890, pp. 435-546; and 1891, pp. 15-114 & 559-662, plates 5, 7,8, & 16. |