520 AN INTRODUCTION TO ENTOMOLOGY 



and wild plants, being practically omnivorous, and in the larval state 

 feeds on the roots of grasses. It was first observed in this country in 

 a limited area in Burlington County, New Jersey, in 19 16, and has 

 since spread over other counties of this state and into Pennsylvania. 

 The adult insect is about the size of the Colorado potato-beetle, but 

 slightly longer. The head and thorax are shining bronze-green in 

 color, with the wing-covers tan or brownish, tinged with green on the 

 edges. Along the sides of the abdomen are white spots, and two very 

 distinct white spots at the tip of the abdomen below the wing-covers. 

 The larva resembles the larvse of May beetles. 



This pest is regarded as of so great importance that a special 

 laboratory, "The Japanese Beetle Laboratory," has been established 

 for investigations regarding it at Riverton, N. J. 



IV. The rhinoceros-beetles. — The name rhinoceros-beetles was 

 suggested for this group by the fact that in many species the male 

 bears a horn on the middle of the head. In addition to this horn 

 there may be one or more horns on the thorax. These beetles are 



of medium or large size ; in 

 ___ fact, the largest beetles 



known belong to this group. 

 As with the flower-beetles, 

 the claws of the tarsi are of 

 equal size, but the fore coxse 

 are transverse, and not 

 prominent. 



One of the largest of our 

 rhinoceros-beetles is Dynds- 

 Fig- 626. f^s tttyrus. This is of a 



greenish gray color, with 

 scattered black spots on the wing-covers, or, if only recently trans- 

 formed, of a uniform dark brown. The male (Fig. 626) bears a 

 prominent horn on the top of the head, and a large one and two 

 small ones on the prothorax. The female has only a tubercle on the 

 head. This insect is found in the Southern States; the larva lives in 

 rotten wood. In the Far West there is a closely allied species, Dyndstes 

 grdntii, in which the large horn on the thorax is twice as long as in 

 D. tityrus. In the West Indies there occurs a species, Dyndstes 

 hercules, which measures 150 mm. in length. 



Several other genera occur in this cotmtry, in some of which the 

 males have prominent horns; in others the horns are represented 

 by tubercles, or are wanting. The following species represents the 

 latter type. 



The sugar-cane beetle, Euctheola rUgiceps .■ — This beetle is a serious 

 pest in the cane-fields of Louisiana, and it sometimes injures com. 

 Figure 627 represents the adult, audits method of attacking a plant. 



V. The flower-beetles. — The flower-beetles are so called because 

 many of them are often seen feeding upon pollen and flying from 

 flower to flower. These beetles are somewhat flattened, or nearly 

 level on the back; the claws of the tarsi are of equal size and the 



