THE BIRD TICK. 99 
TABLE XXIX.—Engorgement of larve of Hemaphysalis chordeilis. 
Larvee dropped engorged—days 
Date N following application. Total 
larvee Host. har? number | State of engorgement. 
applied. dropped. 
5 | 6 7 She 9 4 LOM tela ene 
| 
1909. 
Sept. 7| Rabbit........ 51] Maul) al] ol Bi) eh] oul ao 21 | Fully. 
Beptsmet | Hels. ..c-os55- i Ol Ol GIO Ol Owl w 0 
Sept. 17 | Guinea pig. . 75 Se Sree td eer be clan mae ot 2) Fully. 
Sept. 18 | Hen=...:-:=-% Dee Ol Oi Ol | On OF Os EONS 0 
Sept. 22 | Rabbit........ A AD) OM ON ee tt hy ihe) eo 3 | Two-thirds to fully. 
Sept. 24 |..... Obert one. TEE (OM OO OI esa) ery ale ayy a 7 | Two-thirds to fully. 
Total... P72 1iy NSS ie Seer Meee) eee ere ere eee 33 
At a mean temperature of 79.05° F. molting began on the four- 
teenth day after dropping. When the mean temperature fell to 
53.98° F. 76 days elapsed before molting began. This and the other 
long molting period given in the table were recorded on larve col- 
lected from wild hosts, and although the state of engorgement of the 
ticks was not recorded, there is little doubt that they were not fully 
engorged. This would tend to lengthen the molting period as has 
been ‘found true in all observations made by us on this point. A 
total effective temperature of 505° F. appears to be required for this 
transformation. 
TaBLE XXX.— Molting of engorged larvxe of Hemaphysalis chordeilis. 
Temperature from 
Engorged larve molted—Days following dropping. dropping to date 
first tick molted. 
Date Num- 
pumazeed Host. nee fn | alae | i | i 
dropped. GINTESO ||" || Total ol Parse ver- 
14|15|16| 17] 18 | 19|21| 26|32|42| 67/76 eoee Meee | Mi ae 
| eae 5 y Bias! 
| : 
1909 | | 9 cet Naas SIN i 
Sept. 12] Rabbit.| 6 He: |b Tipe 0 Seal Saelkee saa-c| 3 | 98.50 | 59 79.84 
Sepia ndomee | Ob gl IN eee) ee 11 Goose aii leea a Eee S| 6 | 96.50 | 59 79.05 
Sept. 14 4do28 2 UO eal Sale wel te ales rere ee 1 | 95.50 | 56 77. 28 
Sept. 17 -(i y= 2 oi 1 Be | ae ae 2 | 95.50 | 56 6.75 
Sept. 25 -do.. | avo) ecnilosolseclbes Bee ey |) | =e | 1} 92.50 | 51 72. 38 
Sept. 30 |...do.. ba | Celt 2 hal hell ie 1 | 92.50 | 51 72.77 
Oct 2 -do.. 2 | 1 |e at! nae 2 | 92.50 | 52.50 73. 80 
Oct. 3 Soles 0) A Boal Seeleeel msl eeetiaes else ae 1 | 92.50 | 52 72.88 
NG yiPRL64| Loh! <n a0 CAE eu Cae EE eae oe 04) F18) 2| 79 20 53. 98 
Nov. 25 | Meadow- 
Rete Sa PAARL S| CCEA Se ICSI ESR a eee. (2 ee a Seek 4| 79 20 52.96 
Sine SADR Se Ae ce |e oe We om (eed ae De Pa BSN) ee Aek| Shhh ee 
————— - | —s 
1 Three of these molted before Jan. 31, 1910, and one on that date. 
The nymph (Table XX X1).—On account of the sparsity of material 
at hand, our records on the longevity of nymphs are league ny 
One nymph which molted from a larva about January 22, 1910, was 
alive on April 6, 1910, when it was put on a host. This indiyidenl 
had lived 74 days, which is the longest period recorded by us. One 
nymph which molted February 15, 1910, died 16 days later. Two 
