NOTES ON INDIAN WAGTAILS. 
1085 t 
M. 
calcarata 
M. 
citreola. 
M, melanO’ 
griseu^. 
M. 
heema. 
M. ' 
calcarata. 
Bill exposed 
13-14-5 
11-25-12-5 
as in 
citreola 
as in 
citreola 
-62= 16mm. 
Tail 
74-81-5 
once 84 
72-77 
67-76 
70-5-73-5 
Hind claw 
12-15-5 
once 11 
10-12 
once 13 
as in 
citreola 
as in 
citreola 
44= 11mm. 
The name calcarata of Hodgson for one of the Yellow-headed Wagtails has 
been dropped as it M'as considered that, as Hodgson described a winter bird, 
it could not be said which of the two Wagtails he had before him and therefore' 
Gould’s later name citreoloides* was substituted and used in the Fauna and other 
works. But a careful examination of Hodgson’s original description reveals 
that his calcarata must have been citreoloides and not citreola ; not only does 
of course the name itself suggest that he had before him a bird ■with an out- 
standingly long hind claw but his measurements at once reveal that they could 
not apply to citreola. His bird -with a tarsus of 1'19 (=30mm.) could only be' 
citreoloides. One does not know how he measured the bill so this measurement is 
of little account. His measurement of the hind claw is short and I find that 
this measurement varies according to the time of the year. In autumn and 
early ■winter the hind claw is longer as a rule than in spring and summer in all 
Wagtails, this is due to wear or breaking off of the very slender tip and in such 
examples of citreoloides the hind claw often measures about 12mm. whereas 
autumn birds have the hind claw about 15mm. 
The measurement of the tarsus and middle toe ■with claw is not a very easy 
one to take and no doubt different people would get different results on the same 
specimens according to where they considered the tarso-phalangeal joint to be 
(not always easy to see in a dry skin), but ■with care this measurement can be 
done witb accuracy. Measurement from the tuberosity of the tarsus on its 
outer side to the tarso-phalangeal joint ■will give the longest possible tarsal mea- 
surement, from this last (marked) point measure ■to the tip of the middle claw 
with the toe well extended. Though these two measurements may differ accord- 
ing to different observers, the sum of the two measurements should correspond, 
and it will be seen from the table given that in citreola the sum of the two varies 
from 43-47 and in citreoloides from 48’7o-53mm. This distinction holds for 
both sexes. 
II. — Yellow Wagtails. 
H the Yellow- headed Wagtails can be differentiated with fair certainty the 
. same cannot always be said for the rest of the Yellow Wagtails except for the 
adult males ; ■with females and more particularly with first ■winter birds the 
difficulty in many cases is to find specimens which from the locality in which 
they were obtained can only belong to one form, (for instance Yellow Wagtails 
obtained in Northern Scandina'via could only belong to the race thunhergi as 
no other form occurs there,) and some of these basic guides (if I may so call them) 
do not seem to be represented in any collection. 
® Citreoloides of Hodgson was a 'nomen nudam. 
