1893,] Classification of the Longipennes. 237 
Alca. Huxley has already shown that in another direction 
“the Gulls grade insensibly into the Procellariide ” (P. Z.S. 
1867, p. 445), and it is now generally admitted that through 
an easy gradation, the osteological characters of a Gull or 
Tern, pass into those of the Plovers and their allies among the 
Limicole. 
_ Beyond the Plovers, we are led on the one hand to the Rails 
through the Otididz, the Cranes, the Rhinochetidx, and the 
Psophiide, while on the other, through other branches we 
find the Plovers linked by Hemipodius with the Galline. 
