ARDEOLA RUSSATA. 185 
of their being smaller tlian H. alba, serves as a good distin- 
guishing mark for the species. The total length is about 
24 inches. 
257. Ardeola RUSSATA, Wagl. The Buff-backed Heron. 
Moorish. Tair el bukkar (the Cow-bird). Spanish. Garra- 
patosa, Purgabueyes. 
" This is the most common of the Herons around Tangier, 
and keeps in small flocks, always following herds of cattle, 
often sitting on their backs, and chiefly feeding on insects. 
A small proportion remain during the breeding-season ; but 
the majority pass northwards in February, March, and April, 
returning late in the year." — Favier. 
The Buff-backed Heron is very common in low-lying 
districts in Andalucia, and some are resident; but they are 
very irregular in their movements, and chiefly noticed, while 
passing, during March and April, as they always attend 
cattle when in wet marshy ground. The Spanish herdsmen 
naturally object to have them molested, especially as there is 
a story of a sporting Briton from Gibraltar having shot one 
as it sat on a cow^s back — a story which I am afraid is founded 
on fact, and only shows what the Englishman is capable of. 
The local names of this Heron all originate from its habit 
of attending cattle and freeing them from parasites — Garra- 
patosa from garrapata, a tick or louse ; Purgabueyes, cattle- 
cleaner or purifier. 
A male bird, which had been kept alive for about four years 
in the patio of the Fonda de Europa, at Seville, during the 
first week in April (his fifth spring, as far as I could ascer- 
tain) began to change the colour of the legs and the basal half 
of both mandibles to a pinkish red ; the irides also changed 
to beautiful rich pink colour, with a very slight golden ring 
round the black pupil. This change was quite completed 
before the bird had fully assumed the buff-coloured back, 
which is the mark of the breeding-dress. 
A female, in confinement with the above mentioned, has 
laid many eggs of a very pale bluish- white colour, showing 
a greenish tint inside when held to the light. 
