18 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



DIPLOPODA (Class) 



THOUSAND-LEGGED WORMS 



These so-called "worms" are easily recognized by their cylindrical 

 or semi-cylindrical bodies, which are rather hard and made up of a 

 large number of joints. The antennae are short and there are two pairs 

 of short legs to each segment of the body. The mouth parts are not 

 adapted for biting any hard object, as they are provided with a series 

 of combs, by means of which they comb or scrape off soft decaying 

 organic matter. 



THE COMMON MILLIPED 

 Julus hesperus Chamberlin" 



(Fig. 17) 



Description.— The mature 

 color, often nearly black, 

 and average about one half 

 inch in length. The im- 

 mature forms appear the 

 same as the adults, except 

 in size and lighter color. 



Life History.— Very lit- 

 tle is known concerning 

 the life history of these 

 animals. They usually live 

 in damp places in decayed 

 vegetable matter, upon 

 which they feed. Occa- 

 sionally, however, they are 

 found in plants near or in 

 living tissue. Whether the 

 initial injury is caused by 

 the millipeds or some other 

 animal has not been defi- 

 nitely proven. Dr. Cham- 

 berlin informs lis that the 

 mouth parts do not admit 

 of biting hard materials, 

 but are constructed more 

 for scraping. There is 

 probably a single genera- 

 tion a year, which starts in 

 the spring. 



Nature of Work. — The 

 exact amount of damage 

 done by these millipeds is 

 only a matter of conjec- 

 ture. However, as they 

 are usually to be found 

 present in all cases where 

 they might be suspected, 



millipeds are of a rich chestnut brown 



Fig. 17. — The common milliped, Julus hesperus 

 Chamb., in a head of lettuce. Natural size. (Photo 

 by Leroy Childs) 



"Determined by Dr. R. V. Chamberlin, Dept. of Zoology, Harvard University, 

 Can., Ent. XLVI, pp. 314-315, 1914. 



