BIKD-LIFE OF THE SPANISH SPBING-TIME. 273 



The Bittern lays its pheasant-like eggs in April, often in 

 March ; the Little Bittern not till June. It is difficult to 

 fix a date for the rest — so uncertain are they, and so 

 dependent on the seasons and the quantity of water in 

 the marismas. We have eggs of the Night-Heron taken 

 as early as May 20th — another year none were laid till 

 June 8th. From this latter date onwards is perhaps the 

 average time for eggs of that species, as well as those of 

 the Egret, Buff-back, and Squacco Herons, and the Little 

 Bittern. 



So retiring are the nocturnal species that it is difficult to 

 flush them without a dog ; yet they cannot compare, in 

 this respect, with their neighbours, the Crakes and Bails, 

 which also abound in the Spanish morass — the Water-Bail 

 and Spotted Crake most numerous, Baillon's Crake rather 

 less so, and the Little Crake the scarcest. All these are 

 pointed and ' roded ' keenly by native dogs, but their 

 skulking powers are a match for the staunchest. Mata- 

 perros — " kill-dogs " — is their Spanish nickname, their 

 tbin, curiously compressed bodies resembling in section 

 that of one's hand held vertically, enabling them to glide 

 like rats through the thickest growth of flags and aquatic 

 herbage. 



The nests of all the Bails are hard to find ; but to identify 

 the precise owner of each is a thousand-fold harder. 

 Nests and eggs of all being closely alike, an unidentified 

 clutch is worthless ; but the man who can work this out 

 knee-deep amidst mud and stagnant water, under a broil- 

 ing sun, has patience that nothing can withstand, nor 

 any obstacle resist. 



During May a clamorous element is added to the bird- 

 life of these lagoons by the nesting-colonies of Terns, 

 which hover round the intruder, filling the air with their 

 harsh vociferations. Santolalla is a stronghold of the 

 Whiskered and Black Terns (H. hybricla and H. fissipes) 

 whose nests are built on the water-lilies and floating water- 

 weeds. There are other large colonies in the open marisma, 

 where the Gull-billed and the Lesser Terns also nest, the 

 former in some numbers. 



