October, ’24] 
VORHIES: CYLINDROCOPTURUS JATROPHAE 
527 
and around, but not necessarily completely encircling the stem, and 
seems to at times go into the stem to or through the center. It appeared 
later to work downward gradually and by the time it is full grown is 
making a brass-filled tunnel nearly 1 mm. wide. Pupation as observed 
occurred in the central pith, but whether always so cannot be stated. 
The plant is so weakened by even one larva as to break off readily, 
usually at a point an inch or more below the soil surface, leaving a few 
roots above the point of breakage. One fresh pupa was observed to 
transform into the adult in one week. Stems infested with two or more 
larvae are likely to have a swollen portion above the breakage point with 
the bark broken and having a diseased appearance. The stem may be so 
riddled as to be readily broken through at this swelling. From one 
rather large infested stalk examined with reference to depth of pene¬ 
tration it was found that none had penetrated more than two or two and 
one-half inches below the soil level. 
Specimens sent to Washington for identification were determined by 
Schwarz to be Cylindrocopturus jatrophae Fall., of the sub-family 
Zygopinae, family Curculionidae; and the further surprising informa¬ 
tion was secured that it was first found by Dr. Schwarz himself on the 
south slope of the Santa Catalina Mts., some 15 miles from Tucson, on 
the stems of Jatropha macrorhiza. I say surprising, because Jatropha 
is a Euphorbiaceous shrub, quite unrelated to Chrysanthemum.^ A 
recent examination of Jatropha plants disclosed that some of the stems 
of each clump were dead, and these were found to be mined extensively at 
the crown with frass-filled tunnels closely resembling those found in the 
damaged Chrysanthemums. No specimens were found at this time. 
No further infestation in the affected plot has yet been observed^this 
season. This infestation was the only one that came to the writer’s 
attention last summer, though chrysanthemums are quite commonly 
grown in Tucson. Furthermore, this occurred only one city block, 
actually about 360 feet, from the writer’s chrysanthemums which were 
unaffected. Whether further infestations occur will be a matter^to 
watch with interest. The nearest probable occurrence of Jatropha^ to 
the city would be at a distance of about three miles, in the Tucson 
Mountains. 
FACTS CONCERNING PERIODICAL OUTBREAKS OF 
THE BEET LEAFHOPPER 
By H. E. Severin, University of California , Berkeley , California 
(Paper not received) 
