. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE ROUGH-HEADED COEN STALK-BEETLE 27 head is of a distinctly reddish color but, unlike E. rugiceps, the head is smooth or at most but slightly rugulose, lacking almost entirely the deep pimctures which are so conspicuous in the latter species. (PI. Ill, A and B.) Furthermore, in the larva of L. gibbosus there is no trace of a median double row of modified bristles on the last ventral segment, such as occurs in E. rugiceps. (PL III, D and E.). Fig. 13.—Ventral view of head re- gion of pupa of Ligyrus gib- bosus, showin
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE ROUGH-HEADED COEN STALK-BEETLE 27 head is of a distinctly reddish color but, unlike E. rugiceps, the head is smooth or at most but slightly rugulose, lacking almost entirely the deep pimctures which are so conspicuous in the latter species. (PI. Ill, A and B.) Furthermore, in the larva of L. gibbosus there is no trace of a median double row of modified bristles on the last ventral segment, such as occurs in E. rugiceps. (PL III, D and E.). Fig. 13.—Ventral view of head re- gion of pupa of Ligyrus gib- bosus, showing structure of mouth parts. (Drawn by Henry Fox from, a photograph by J. H. Paine) The pupa of L. gibbosus (PI. IV, B) is distinguished from that of E. rugi- ceps by certain . characters associated with the mouth parts, by the form and position of the postcoxal process of the presternum, and by the prominent bi- costate elytral pads (PL IV, A and Z?, and figs. 4 and 13). The mandibles (fig. 13) are much smaller and slen- derer than those of E. rugiceps, and are further characterized by the truncate, not angulate, apex which lies in contact with the nearly straight sides of the labrum. The maxil- lary palpi are also shorter and rather more rounded at the apex than in E. rugiceps. The postcoxal process of the presternum is less nearly erect and the apex is rather more acuminate than in E. rugiceps. In general form and size the adult of L. gibbosus (fig. 14) resembles that of E. rugiceps, but is usually distinguishable at a glance by its reddish brown color and by the distinctly hirsute character of its ventral surface. Occasionally adults are found in which the color is so dark as to be almost black. The most reliable differential character is the presence in L. gibbosus of a median pit or depression close to the anterior margin of the pro- notum, which is entirely lacking in E. rugiceps. In front of this pit is a blunt spine or tubercle. Other distinguishing characters of L. g
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