THE CAYENNE TICK. 157 
a second lot of females was applied and had become engorged. When 
attached the entire length of the hypostome is buried in the flesh, 
the palpi bending back and touching the anterior part of the scutum. 
TaBLE LXX.—Engorgement of females of Amblyomma cajennense on bovine. 
Engorged females dropped—days 
following attachment. Total 
Adults applied. Date of attachment. number 
dropped. 
7 8 9 10 11 
BE Dingo LOO ie se aoe eee ioe | ac eeninieere sic eae a= oc Meee Pod” 3 | OS (ete ape ss 2 
Bisans9, W908 est cece st ash | sac Pokus c sels te eee ee ES Ra eer See Oe ase © eee 4 1 5 
PLY O; LOUD aie whe ayosage wap JD See ae eee Be Pee Tas ieee i tt ees of 2 
Tula Dil ONO Sz aeeest ek 3k AG) Rahal EW be be Se eed ee ee Uses aera eee 1 Ras ss: 2 
DQpb. 13,0009. 2 -5..2o2st he SOpbs Wee tee se ee ee ee a alae sad eke os olla v et 2 1 3 
Ob. .assacietttass SSeenc8 ola) ULE, 7 a eee eget Meee Us eke Ses St, Seeks esate ae 9 1 
otal ss ce vs 25. 5 Peer eA chee Sees Scheer goles - 15 
LIFE CYCLE. 
Larve may live as long as 386 days. In summer they may en- 
gorge in 3 days and molt as soon as 10 days after dropping. A total 
effective temperature of 468° F. appears to be required for this trans- 
formation. Nymphs may live more than 134 months if they do not 
find a host; they engorge as soon as 3 days and molt as soon as 12. 
days after dropping. The nymphal molt requires an accumulation 
of 558° F. of effective temperature. Adults may live as long as 466 
days if they do not find a host; they may engorge as soon as 7 days 
after attachment, commence ovipositing 9 days later, and deposit as 
many as 4,789 eggs. The eggs require 1,370° F. of effective tem- 
perature for incubation. 
ECONOMIC IMPORTANCE. 
In this country cajennense is of economic importance in the lower 
Rio Grande Valley of Texas only. In the vicinity of Brownsville it 
is very abundant at certain seasons of the year and is the source 
of great annoyance to horses, mules, cattle, and other domestic 
animals. Stoll (1890) states that in Guatemala the larve of this 
tick hang on the grass in clusters of thousands, and are the source 
of great annoyance to travelers. The collection of the Bureau of 
Entomology contains many specimens taken by Schwarz and Barber 
in Guatemala, upon their bodies. December 5-8, 1909, Schwarz and 
Bishopp found this species to be very abundant in all stages at Tam- 
pico, Mex. All stages were found in great abundance on horses, and 
in much smaller numbers on mules, donkeys, and cattle. The adults 
are especially bad pests to these animals. Many people stated that 
it was necessary to apply kerosene and lard to their horses at frequent 
intervals to lessen the number of ticks on them. While collecting 
insects in the vicinity of Tampico, these ticks proved very annoying. 
At times the trousers of Schwarz and Bishopp were covered with 
thousands of larve, many of which gained access to the skin and 
attached. Although much fewer in number, the bites of the nymphs 
