302 
Fleas on Rodents 
For the purpose of these determinations that part of the animal 
lying in front of the fore legs was called “ head and neck.” The “ hind 
quarters” included everything posterior to the middle of the trunk, and 
the parts lying between this and the “ head and neck ” was called the 
“ fore quarters.” 
A summary of the three tables, including a total of 230 rats, shows 
the percentages of species of fleas as follows : 
Fasciatus 
Cheopis 
Musculi 
Head and Neck 
3-3 % 
7-7 °/o 
87-2 «/„ 
Fore Quarters 
10-5 
6-8 
12-2 
Hind Quarters 
86-2 
85 - 5 
*6 
Distribution of squirrel fleas (Ceratophyllus acutus) on rats. 
Fore Quarters 
C. acutus 
No. in ^-*-- 
Group Host M F 
9 Mus norvegicus 1 1 
Total both sexes 2 34 
Percentage 6 94 
Hind Quarters 
C. acutus 
F Total 
18 16 38 
Distribution of squirrel fleas {Ceratophyllus acutus and Hoplopsyllus 
anomalus ) on squirrels (Citellus beecheyi). 
Head and Neck Fore Quarters Hind Quarters 
No. in 
Group 
C. acutus 
Anomalus 
C. acutus 
Anomalus 
C. acutus 
Anomalus 
Host 
M 
F 
M F 
M 
F 
M 
F 
M 
F 
' M 
F 
Total 
ii 
C. beecheyi 
19 
16 
— — 
38 
58 
— 
— 
93 
118 
— 
— 
342 
8 
> > 
5 
— 
— — 
37 
44 
2 
— 
42 
31 
— 
— 
161 
6 
5» 
14 
16 
—’ — 
15 
26 
— 
4 
33 
39 
8 
23 
178 
25 
33 
37 
— — 
90 
128 
2 
4 
168 
188 
8 
23 
V > --- V -✓- r - V V 
Total both sexes 70 218 6 356 31 681 
From this we find that the percentages are as follows: 
C. acutus H. anomalus 
10-9 o/ 0 
33-8 
55-3 
Head and Neck 
Fore Quarters 
Hind Quarters 
00-0 o / 0 
16-2 
83-8 
