CRIBRATRICES. 
143 
by most authors, they have been comparatively neglected. 
They may be divided into three very natural orders, namely, 
the Cribratrices, or Sifters ; Urinatrices, or Divers ; and 
Mersatrices, or Plungers ; each of which may be subdivided 
into very natural groups or families. 
ORDER XVII. CRIBRATRICES. SIFTERS. 
The birds of which this order is composed are those 
known by the familiar names of Geese, Swans, Ducks, 
Teals, Wigeons, Pochards, Shovellers, and others, toge- 
gether with the Flamingoes and Mergansers. They all 
agree in having the bill covered with soft skin, the only 
hard or horny parts being the two ungues, or nail-like 
bodies, situate one at the tip of each mandible, and in 
the presence of numerous transverse or oblique elevated 
lamellae on the inner side of both mandibles, at the mar- 
gins of which they are generally enlarged, and assume 
various forms in the different species, of which the bill 
may thus be described as marginally lamellate, pectinate, 
serrate, or denticulate. The families of the Cribratrices 
are the Phcenicopterxnje, composed of the genera Phoe- 
nicopterus and Cereopsis, neither of which have repre- 
sentatives in Britain, Anserine, Anatinje, Fuligulinjs, 
and Mergax SE iuxiE . The birds of the first of these 
orders resemble some of the Waders in form, and those 
of the last approximate to the Divers. The general cha- 
racters of the order, briefly stated, are the following 
Body large, full, and muscular ; head oblong, com- 
pressed. Bill never very long, sometimes short, cerate, 
with internal or marginal lamellae. Tongue fleshy, large ; 
