KATYDIDS INJURIOUS TO ORANGES IN CALIFORNIA. 



The Young. 



GENERAL APPEARANCE. 



Fig. 4.— The fork-tailed katy- 

 did (Scuddtria Jure at a): 

 First-instar nymph. About 

 three times natural size. 

 (Original.) 



The young katydids of this species vary in length from one-sixth 

 to three-fourths inch, depending on their age. Immediately after 

 issuing from the egg they are of a pale flesh 

 color, without visible vestige of wings. The 

 head and mouth parts are large in proportion 

 to the rest of the body; the antennas are long 

 and slender and usually directed forward. The 

 larger nymphs, with rudimentary wings or 

 '"wing-pads," are bright green, closely match- 

 ing the color of the orange leaves on which they 

 rest. They resemble somewhat the young of 

 the short-horned grasshoppers (Acridiidas), ex- 

 cept for the long, slender antennae. They usually remain motionless 

 upon the leaves or move over to the side away from the observer when 

 too closely approached. Ordinarily at the approach of danger they 

 become perfectly motionless in every part and, simulating the leaf 

 color closely, are readily overlooked. When sufficiently disturbed, 

 however, they show ample power as leapers, and will jump 

 a foot or more. 



DESCRIPTION OF INSTARS. 



The young katydid grows slowly for an average period 

 of about 73 days, during which time it molts six times 

 before final emergence as a mature insect. 



First instar (fig. 4). — Measurements: Greatest breadth 

 of head, 1.10 mm. ; greatest breadth of abdomen, 0.75 mm. ; 

 length of body, 4.10 mm.; length of pronotum, 0.70 mm.; 

 length of posterior femur, 4.20 mm.; length of antenna, 10 

 mm. Just after issuance from the egg the nymph is of a 

 antenna of pale flesh color. The legs, head, and thorax are irregularly 

 '" ' r marked with small blotches of red, purple, and white; the 



mph. 11 i • i • i p i 



Greatly en- abdomen . with about ten longitudinal rows ol minute red 

 :irk '"' 1 and while spots, the most conspicuous of which are one 

 low of dark spots on either side of the middorsal yellow 

 line and two rows of white spots below these on either side of the abdo- 

 men. Tli" newly issued nymph is about one-sixth inch long. The 

 fastigium, which is most prominent in this stage, is about one-half as 

 long as the club-like basal segment of the, antenna (fig. 5). Antenna with 

 five distinct, broad white pings at regular intervals from tip to base, and 

 with i wo narrow . Le 3 di tinct white rings near i he base; spaces between 



t he rings dark purple. I lead broad, I hora.\ comparal ively narrow, ab- 

 domen considerably enlarged toward I ip. The Lateral edges of sclerites 



