'I'llE MONTHLY BDLT.KTIN. 



189 



NOTES ON THE TOMATO PSYLLA. 



By riARoi.D Compere. 



Specimens of Paratrioza cockerelli Siilc, a .small Ilemipterous insect 

 belonging to the family Psyllida?, were confined in the Insectary for 

 the jMirpose of rearing their parasites. Incidentally, a few observa- 

 tions on tlieir habits were made which are noteworthy. 



Psyllids are intermediate in form, between the scales and plant lice 

 on the one hand and cicadas and larger plant bngs on the other. The 

 adults have gained the name of jumping })lant lice because of tlicir 

 habit of springing ({uickly into the air by means of their powerful 

 hind legs. When once in the air flight is maintained by the wings, 

 although they seldom fly more than a few feet. 



The specimens were determined by D. L. Crawford, who, in his 

 monograph of the Psyllidie of the world, gives the distribution of this 

 species as covering the entire southwestern part of the United States, 

 and lists the following eight hosts, although all of these may not be 

 true food plants: pepper (Capsicum anuum), tomato [Solanum 

 nigrum), jootato {lSola)iU:m tuberosum), Pursliia sp., arbor vitae {Thuja 

 occidentalis), spruce (Picca sp.), pine {Pinus monophylla), alfalfa 

 (Medicago sativa). Crawford says that this insect is often found in 

 great numbers, sometimes becoming a pest to cultivated plants. Our 

 specimens were found in the Capitol Park infesting the Jerusalem 

 cherry {Solanum capsicastrum) . In Golden Gate Park. San Fran- 

 cisco, the solanums that were infested with this Psylla were rendered 

 worthless. 



THE ADULT. 



The adult is a small, active, clear-winged insect greatly resembling 

 a miniature cicada or harvest fly. Like the latter, the wings are held 

 roof-like over the back. The color is variable, but this species can 

 easily be distinguished by the striking coloration of the body. The 

 ground color is usually dark, the markings varying from white to 

 gray in color. 



Feeding Hahiis. — The feeding habits of the adult are about the same 

 as those of the nymph, except that the adult shows more activity. The 



Fig. 62. — Adult of Para- 

 trioza cockerelli Sulc. En- 

 larged about 12 time.s. 

 (Original.) 



Fig. 63. — Egg of Para- 

 trioza cockerelli S u 1 c . 

 Greatly enlarged. (Orig- 

 inal.) 



adults are present at all seasons and easily located. Wiu-ii approached 

 they try to conceal themselves among the stems and leaves before 

 In cajitivily they lived more than one month. 



taking flight 



