54 AUSTEALIAA" SUGAR-CANE BEETLES AND THEIR ALLIES. 



LEPIDIOTA 8P. 



Known to ns only from the neiglibonrhood of Atherton, 2,500 feet. 

 Cairns district, this member of the genus is somewhat smaller than 

 frenchi, and the elytra are light polished brown in colour. The adidts 

 T^vvarmed in vast numbers in January and February. 



The species is of especial interest because of its depredations in 

 grass paddocks near Atherton. Just behind the town near the show- 

 ground, there is a paspalum paddock of about 30 acres, owned by jMr. 

 A. Arnott, and early in ]March, 1921, when we visited the district it was 

 a pitiable sight. One-third was quite dead, in great bare patches devoid 

 entirely of grass, the remains of the shrivelled-up stocks lying on the 

 surface, the roots having been completely eaten away; of the rest of 

 the paddock much was very poorly and none bore a sturdy crop. 

 Examination showed that the whole paddock was thoroughly infested 

 with Lepidiota grubs, which were in great numbers within an inch or 

 two of the surface, and thus often at the very stocks of the grass. In 

 the denuded areas they were quite as plentiful as in the grassed areas. 



On 15th I\rarch Mr. Arnott wrote— 



''As far as I know, these grubs have only attacked paspalum. and 

 I only know of a few paddocks aft'eeted besides my own. I tirst noticed 

 the effects of the grubs aljout eighteen months ago, wiien the grass was 

 a trifle yellow in patches; this season nearly half the paddock (of 30 

 acres) is eaten clean out and the balance is swarming with grubs. Corn 

 is growing alongside, but does not appear to suffer. The grubs in the 

 dry season are down from 2 to 4 feet in the red soil. I was sinking a 

 well in October and found scores below 3 feet. They rise to within a 

 couple of inches of the surface after the first heavy rains and shortly 

 after (about the first week in January) the beetles appear and fly 

 after dark. The flights only lasted about five weeks; after that only 

 odd beetles were met with and now it is very rare to come across one. 

 They do not appear to have any natural enemies in the ground; of 

 course the birds eat them if they are exposed. I notice quite a lot of 

 baby grubs hatching out lately but have not noticed the eggs. Should 

 these grubs take to the corn lands, they would do an enormous amount 

 of damage ; it will only be a short time before the bulk of the paspalum 

 is eaten out of the infested paddocks. ' ' 



"We were informed by others, that in other fields in the district 

 small patches of grass have been killed in this way for some years, but 

 the damage has been negligible. 



The Grid). — On 6tli March most of the grubs were in stage III, and 

 a few stage I were observed, but no stage II. On 25th March Mv. 

 Arnott sent twelve grubs, eleven in stage III. one in stage I. Since 

 they are in stage III and doing their main damage in January and 

 February, there is little doubt that this species, like all those closely 

 related to L. frenchi, has a two-year life-cycle. 



The stage III grub is hardly differentiated from that of L. frenchi 

 except by its distinctly smaller size, the width of the head being 5-5 mm. 

 in comparison with the 6-5 mm. of the named species. Thus it 

 approaches, at least in size, nearer to the species designated by Girault 

 and Dodd as No. 666, but there are at least six hairs on either side in 

 the irregular row inside the epicranial sclerite (two on either side in 

 .No. Gm). 



