HEEODIONES 431 



have a long large intestine. As a rule the left lobe of the 

 liver is the smaller, vs^hile in the storks the lobes are equal. 

 A gall bladder is always present except in BotowrMs stellaris. 

 The caecum is single, and, as will be seen from above 

 measurements, rudimentary. 



The carotids are, as a rule, two, and separate ; but in 

 Botaurus they fuse, and in Ardetta involucris the right only 

 is present. 



Of the leg muscles the amhiens is always absent, and the 

 formula is typically AXY— . The femorocaudal is never 

 strong, and is particularly slender in Ardea Goliath} In A. 

 sumatrana, A. ludoviciana, Nycticorax Gardeni, Cancroma 

 cochlearia, and Tigrisoma brasiliense it is totally absent. 



The deep plantar tendons are characteristic ; there is 

 almost always a very slender vinculura between the two, 

 which is totally wanting in Botaurus stellaris, Ardetta 

 involucris, and A. exilis. 



The tensores patagii are stork-like. The tendon of the 

 brevis bifurcates, and from the point where the anterior 

 limb is inserted on to tendon of extensor of fore arm a 

 recurrent slip is given off to longus. This arrangement 

 holds good for Ardea purpurea, A. Goliath, Cancroma 

 cochlearia, and Nycticorax griseus ; but in Cancroma the 

 recurrent slip is sometimes absent. The pectoralis abdomi- 

 nalis is present, and thus serves to differentiate them from 

 the storks, ibises, and spoonbills, in which the muscle is 

 absent. 



The skull of the Ardeidse has been chiefly studied by 

 Shufeldt.^ In the more normal forms (e.g. Ardea cinerea, 

 Butorides cyanurus) the skull is holorhinal, the holorhiny 

 not being obscured — as it is often among the storks — by 

 the irregular ossification of alina'sals. The vomer is well 

 developed, much compressed laterally, and largely double. 

 The maxillo-palatines are spongy bones, largely free 

 from each other posteriorly. The palatines (see fig. 202) 



' Sometimes absent in this species. 



2 ' Osteological Studies of the Subfamily Ardeina;,' Journ. Comp. Med. and 

 Surg. 1889. 



