86 KANSAS UNIVERSITY SCIBNCK BULLETIN. 



of the fabric, dropping the fragments into the deep cavity that 

 has been made by the animal. Then the ibis retires a single 

 step and patiently waits the result. The crayfish, encumbered 

 by the load of earth, instantly sets to work anew, and at last 

 reaches the entrance to its burrow ; but the moment it comes 

 in sight the ibis seizes it with its bill." 



Girard ('52), whose observations were made in the meadows 

 in the vicinit}'- of Washington, published quite extensive notes 

 on the habits of this species. The substance of his observations 

 is given below, quotations being freel}'^ used where condensation 

 seemed inadvisable. 



Of the burrows, he says : "The holes, as they appear at the 

 surface of the ground, are nearly circular, from seven -tenths of 

 an inch to one inch and one inch and a half in diameter. The 

 depth of the burrows varies according to the locations ; this we 

 generally found to be from sixteen inches to two feet, and some- 

 times three feet and more. The construction of the burrow 

 itself is often exceedingly simple ; from the surface of the ground 

 the excavation exhibits a gradual slope in direction, more or 

 less undulating for a distance of from five to ten inches, when 

 it becomes vertical for six or eight inches, and then terminates 

 in a sudden, bottle-shaped enlargement, in which the animal is 

 found, the bottom of the burrow having no subterranean com- 

 munication, no other issue except towards the surface ; it is en- 

 tirely isolated from its neigh bers, and leaves no chance for 

 escape to its inhabitant. The same burrow may have several 

 external holes connected with it, several inclined channels, 

 which, however, meet at a depth where it becomes vertical. 

 We found constantly the cavity full of water, but this was in 

 March and April ; the bottom, for several inches, was filled with 

 soft and pulpy mud." 



"There are other instances of burrows somewhat more com- 

 plex. Their direction may be oblique throughout their whole 

 extent, and composed of a series of chambers or ovoid enlarge- 

 ments, succeeding each other at short intervals sometimes, 

 also, and, connected with one of the chambers, a narrow and 

 nearly vertical tubuliform channel extends downward to a 

 much greater depth, and appears to us as a retreat, either dur- 

 ing the cold winters or else during the dryness of the summer, 

 when the water is low. That it is not for the mere purpose of 



