I1EROD10NES 429 



at their sternal insertion in Leptoptilits. 1 The hypoclei- 

 diuni articulates with carina sterni. The skull is desmogna- 

 thous, holorhinal, and without basipterygoid processes ; there 

 are in Tantnhi^ rudiments of these processes in the shape of 

 a minute spine. The holorhinal character of the nostrils is 

 largely marked by ossifications of the alinasals ; the nostrils 

 are thus much reduced in size, in a fashion suggestive of the 

 Steganopodes and possibly significant, but there is no bony 

 septum between them. This distinguishes the storks from 

 the herons, as does also the form of the palatines. These 

 bones are in the first place not cut off at right angles behind, 

 as in the herons, while the internal lamina only bounds the 

 interparietal space, and is at most (Xenorhynchus) carried 

 back to the end of the bones as a slight median keel. This 

 is absent in other storks. In Xenorhynchus and Lcptoptihi* 

 the palatines again approach each other, and are only sepa- 

 rated by the vomers just behind the maxillo-palatines. Oppo- 

 site to this point each palatine is produced into a strong 

 outwardly directed snag, large in Xenorhynchus, hardly indi- 

 cated in other storks. The interorbital septum is entire. 

 The large lacrymal is perforated or deeply notched for duct 

 of gland. 



Family Ardeidse. The herons contrast with the storks in 

 (1) the tracheo-bronchial syrinx always furnished with a 

 pair of intrinsic muscles, (2) non-division of pectoralis pri/-ux 

 into two layers, (3) invariable absence of ambiens, (4) pre- 

 sence of powder-down patches, (5) absence or weakness of 

 vinculum, ((>) presence of a single cascum only. 



On the other hand the two families agree in (1) absence 

 of biceps slip to patagium, (2) presence of expansor secun- 

 dariorum, in addition, of course, to the points enumerated in 

 the definition of the group. 



In Cancroma the oil gland is nude. The herons have 

 four or six. powder-down tracts. Six are found in Cancronni, 

 Bntorides atricapillus, Anlcu cocoi, and other species; 



1 Not ill Xenorliiincltits and Dissura ; there is a trace of an overlap in 

 Abdimia, Tantalum, and Platalca. 



