436 
Biologn of IxodUlae 
HYALOMMA AEGYPTIUM. 
The following notes supplement those already published {Parasitology, 
VI. pp. 105-110); 
Time the adult tide remains upon host, especially the males. 
On 18. XI. 1913, 12 d and 12 $ were placed upon calf xxii; they 
belonged to the same lot previously reported upon (N. 1305 a). The 
?s dropped off gorged as follows; 4 on day 8, 2 on day 9 and 2 on day 
10; 4 $s were lost. Of 12 ds there remained 9 alive and attached to 
the host until it was killed on 16. i. 1914, i.e. 60 days after they were 
placed on the calf; 3 of the 12 ds were lost. 
Longevity of unfed adults. 
Adidts which emerged on 3. xii. 1912 were maintained at room 
temperature in the laboratory in a jar covered with gauze. On 13. xi. 
1914 they were turned out and examined. The ticks had been originally 
placed in the jar as gorged nymphs of which there were 340. Only 
4 of the nymphs failed to undergo metamorphosis. On the date 
mentioned above, i.e. 710 days after emergence, there were found 
103 (22 d, 81 9) living and 233 (61 d, 172 ?) dead adults in the jar. 
After 759 days there were still 20 d and 47 $ living. A couple of 
$s after fasting 817 days have been fed on a ram, have mated with ds 
that have fasted over 210 days, and are at the time of writing engaged 
in ovipositing H. aegyptium would appear for the present to hold the 
record in the matter of longevity when unfed. 
Proportion of the sexes. 
The adults referred to in the previous paragraph were all part of 
the progeny of a single ? (No. 13) which laid 13,940 eggs; these adults 
numbered 336 and may be regarded as a fair sample. The sexes were 
represented by roundly three times as many females as males: 83 d 
and 253 $. 
HYALOMMA SYRIACUM. 
A gorged ? was brought to the laboratory by Dr E. Kindle some 
days after she had dropped from a tortoise. Oviposition began on 
13. VII. 1913 and lasted 19 days, the 9 dying a day later. The number 
of eggs laid was 6118, and the first larvae appeared 11 days after 
the first eggs were laid. The 9 and eggs were maintained at 30° C. 
(Incidentally I would mention that the lady to whom the tortoise 
belonged mothered the tick for some days in the fond belief that it 
was a young tortoise!) 
