(x. E. Bodkin 17 
It was impossible, owing to the lack of space and equipment, to raise even 
a quarter of the larvae produced from the eggs laid by one female. 
Some of the progeny of these ticks were carefully raised and 65 adult 
females were eventually secured. Some of these were again allowed to engorge 
and produce another generation. I have thus raised, from the two original 
females, four generations parthenogenetically. No diminution either in size 
or vigour was noticed. 
From these results it appears that a generation produced parthenogenetic¬ 
ally consists entirely of females. 
An attempt was made to determine the results of fertilization. 
For this purpose two female ticks (A and B) were selected which for three 
generations back had been bred parthenogenetically. Males were secured 
from the field and copulation was allowed to take place. Fertilization took 
place inasmuch as a spermatophore was in each instance observed to be 
attached to the sexual orifice of both females. 
Of the progeny of ? A, owing to several misadventures, only 6 reached 
maturity; all of these were females. Of $ B’s progeny 15 reached maturity; 
one was a male and the others females. 
It seems likely that a parthenogenetic generation consists entirely of 
females; otherwise a small percentage of males results. Hooker, Bishopp, 
and Wood (1912) obtained a percentage of 71 females in a generation. In 
this instance it is uncertain, however, that fertilization took place. 
REFERENCES. 
Aragao, H. de B. (1912). Beitrage zur Systematik und Biologie der Ixodidae. Mem. do 
Inst. Oswaldo Cruz, iv. 96-119, 2 pis, 6 text-figures. 
Hooker, W. A., Bishopp, F. C. and Wood, H. P. (1912). The Life History and Bionomics 
of some N. American Ticks. U.S. Dept, of Agric. Bureau of Entomology, Bull. No. 106. 
Issued September 7th, 1912. 
Newstead, R. (1909). Ticks and other blood-sucking Arthropoda (in Jamaica). Ann. Prop. 
Med. and Par. in. 421-69, pis. 4, figs. 2. 
Nuttall, G. H. F. (vn. 1913). Parthenogenesis in Ticks. Parasitology, vi. 139-40. (Refers 
to A. agamum Aragao 1912, and experiments with Rhipicephalus bursa.) 
- (hi. 1915). Artificial parthenogenesis in Ticks. Ibid. vn. 457-61. (Parthenogenesis 
experimentally induced in R. bursa.) 
EXPLANATION OF PLATE II. 
(Photographs by G. E. Bodkin.) 
Fig. 1. Amblyomma dissimile, 3<$$, infesting head of Bufo marinus. 
Fig. 2. Amblyomma' dissimile, engorged $, in characteristic position on head of B. marinus. 
Slightly under life size. 
Fig. 3. Amblyomma dissimile, engorged attached to side of body of B. marinus. Slightly over 
life size. 
Fig. 4. Cage used for confining the toads used for raising the ticks. The large dish contains 
kerosene and water. The lead weight holds the lid firmly in place. For description, see text. 
Fig. 5. Tubes used for confining the ticks under experiment. They are planted in damp sand and 
cotton-plugged above. The shallow dish contains kerosene and water. 
Fig. 6. Amblyomma dissimile, ovipositing. About natural size. 
Parasitology xi - 
