20 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



SYMPHYLA (Class)" 



SYMPHYLIDS 



"The members of this class are small and slender with soft, whitish 

 integument and are more or less thysanuroid in appearance. Most of 

 the segments bear a single pair of legs and none bear two pairs. Only 

 twelve pairs are present in the adults and fewer pairs in the imma- 

 ture stages. No eyes or poison jaws are present. The antennae are 

 long and many jointed. At the caudal end of the body there is borne 

 a pair of conspicuous styliform processes or cerci. The reproductive 

 organs open in the anterior portion of the trunk, as in the diplopods. 

 One species in California has proven quite destructive to certain forms 

 of vegetable life and is dealt with separately. No such habits are 

 known for any member of the class elsewhere." 



THE LIMA BEAN SYMPHYLID 



Scutigerella californica (Woodworth)" 

 {Scolopendrella californica Woodworth) 



■ (Figs. 18-20) 



Description. — The full-grown symphylids are pure white in color 

 and exceedingly small, varying from one fourth inch to nearly one 

 half inch in length. There are twelve pairs of legs, the last two pairs 

 being longer than the rest. The anal appen- 

 dages are slightly shorter than the last 

 body segment. There are fewer legs in the 

 immature forms. 



Life History. — The life history of this 

 species is not well known. Normally it 

 evidently feeds upon decayed vegetable 

 matter, but in the spring it attacks planted 

 seeds and vegetables, often doing much 

 damage to the former by preventing healthy 

 germination and growth of the young 

 plants. Mr. E. R. Ong found very young 

 forms in the decaying stubs of asparagus 

 stalks beneath the hard outer skin, in 

 February and March, 1912. There is ap- 

 parently but one brood a year— the young 

 appearing very early in the spring. 



Nature of Work. — The work of this 

 symphylid is very marked and consists in 

 the making of numerous small tunnels 

 through the host, as shown in Fig. 19. 

 This work is done before the plant comes to 

 the surface of the ground. 



Distribution.— The animal is distributed throughout the State, 

 but has proven to be a pest only in the central and southern parts. 



u Written by Dr. R. V. Chamberlin, Harvard University, Cambridge, Mass. 

 "•This species is reported by Dr. R. V. Chamberlin as being apparently synonymous 

 with or extremely close to Scutigerella immaculata (Newport). 



Fig. 18. — The lima bean 

 symphylid, Scutigerella cali- 

 fornica (Woodw.). Greatly 

 enlarged. (After Woodworth) 



