338 



NATURAL III STORY OF ARTHROPODS. 



character in Rhynchophora," ami "the first joint of the funicle rounded, the remain- 

 ing joints (five in number) closely united, forming a i)edicel to the club." ^S'. quadri- 

 sj'x'tiosus, having deeji stri;e, and the male of M-hich has a spiny abdomen, has hcen 

 bred by Dr. C. V. Riley from hickory ( Cari/a) ; its length is about (I.2 of an inch. 

 S.fagi, another deeply striate species, of which neither males or females liave a spiny 

 abdomen, is about 0.2 of an inch long, and was bred by Mr. B. D. Walsh from beech 

 {Fagus). S. rugulosxis, a species lately introduced from Europe into the eastern 

 United States, attacks cherry, peacli, and plum trees ; and, as is so often the case with 

 imported insects, does more damage in its adopted country than it did in its native 

 land. 



The CuECULioxiDiE, the true weevils, are generally compact licetles, of firm struc- 

 ture, often having elytra so hard as to be penetrated with difficulty by an insect pin, 

 and are jirovided with a proboscis pointing forward and down- 

 ward, produced, as in other weevils, by the anterior prolonga- 

 tion of tlie head, and bearing u])on its sides the antenna, which 

 are straight in some sub-families, geniculate in others. The 

 mouth-jiarts, mostly somewhat abortive, are at the end of the 

 proboscis ; the labrum is wanting in many species. The ventral 

 segments are five in number, although tlie first and second ai-e 

 often more or less united, frequently to such an extent as to 

 ])artly obliterate the suture. In some sub-families the sexes are 

 distinguished by the presence in the males of an additional anal 

 segment ; in certain species the females have a longer jiroboscis 

 than the males, the proboscis being used in boring holes in 

 which to lay eggs. Many sjiecies can produce creaking sounds, 

 by rubbing the abdominal segments against the inner surface 

 of the elytra. 



The Curculionidie are remarkable for the great diversity of 

 mode in their ornamentation ; pubescence, j^unctate and striate 

 surfaces, alone or in combination, highly polished or excessively 

 warty surfaces, s\n-faces clothed with pollen-like waxy secretions 

 (as in IJ;rus), all modes of ornamentation common to most 

 families of Colcoptera, are aided in many sjiecies of Curcu- 

 lionidfe by scales, which often surpass in brilliancy those that furnish material for the 

 color-patterns on the wings of Lepidoptera. Especially resplendent under the micro- 

 scope are the scales of the diamond-weevils ('s]>ecies of Entinms) from South America; 

 of species of ChlorojJhanus and Pohjiirosvs from Europe, and of sjiecies of Exoplithal- 

 mus and Eudiagogus from warmer parts of Xorth America. The larvfe of Curcu- 

 lionidne are short, cylindrical grubs, mostly legless or with very rudimentary legs. 

 A few have ocelli. 



With very few exceptions, species of Curculionidfe are phytophagic ; one species, 

 Erirhimis infirmns, is said to have been reared from the bodies of dead insects. 

 Scarcely any portion of plants escapes injury by larvre of weevils; many species live 

 in seeds, in grain, in nuts, in rolled-np leaves, in catkins, in fruit; others bore in wood 

 or pith ; others feed exposed upon leaves or mine in their parenchyma ; a few make 

 galls or gall-like excrescences upon stems or roots, while a number have been observed 

 to feed in plant-galls made by hymenopterous insects; a few breed in fungi. Weevils 

 are found in all kinds of situations ; eyeless species live in caverns or subterraneously ; 



Fig. 37B.—BalaHiniis nv- 

 cum ; side of head beiieatli. 



