238 NATURAL HISTORY ESSAYS 



used in fights amongst themselves at the breeding 

 season. It communicates with a gland which may 

 secrete a poison; at any rate it was on acconnt of this 

 apparatus that the old naturalists conferred the name 

 of Echidna on the species, likening it to the lethal 

 machinery of the reptilian echidna ("ExtSva) or viper. 

 M. M. Quoy and Gaimard were, however, unable to 

 induce their own echidna to wound them with its 

 spur, although they irritated it specially for this 

 purpose. The eggs of these animals are of the size 

 of that of a sparrow : resemble those of reptiles 

 and not of birds, being cased in a leathery 

 white shell like a snake's ; and possess a relatively 

 large yolk. The "new laid ^'g^' is about five- 

 eighths of an inch long and contains an embryo of 

 one-fifth of an inch : it is transferred by the mother 

 to the "brood pouch," a remarkable structure 

 specially developed at the breeding season by 

 the coalescence of two rudimentary folds of skin. 

 The embryo soon breaks the shell with its specially 

 armed beak, "tip-tilted like the petal of a flower,"-^ 

 though it remains in the pouch till about three and 

 a half inches long, at which period the spines begin 

 to appear. Females may be taken with eggs or 

 newly-hatched young in the pouch during the month 

 of September ; by the middle of October these 

 quaint infants may be found in depressions of the 



1 The Cii^-breakinp; tubercle of the echidna may be compared with 

 that of crocodiles and lizards. 



