When is a toad not a toad? Thus the old riddle might readily be paraphrased, and answered with-"when it is a lizard!" This reply is entirely applicable to the horned lizard, for this creature has been called "horned toad" so long and so often that we nearly forget what it really is.
A true toad is an amphibian, by which we mean that it spends the first part of its existence in the water, where it hatches from the egg to undergo a tadpole stage.
The remainder of its life it passes on land, either on the surface searching for food or, during very hot or cold weather, buried deep in the ground.
It resorts to the water again at breeding time to produce eggs and start the cycle all over again.
The horned lizard, as we must really call our spiny friend, is a reptile, and differs in many ways from a true toad.
Some species lay eggs, while others produce living young, which can run about in the sand and fend for themselves from the time of their birth.
A baby horned lizard is in most respects the image of its parents, except that it is smaller and not quite so spiny and roughened in appearance.
A toad baby on the contrary is a rotund blade pollywog which in its early infancy has no sign of legs, but only a large rudder-like tail by which to propel itself; moreover, it breathes oxygen from the water as a fish does, and at this stage would die at once if left exposed to the air.
Among so many unlikenesses, we find nevertheless a certain similarity between this "toad" and true toads in food habits during adult life.
In their natural surroundings, as well as in captivity, both are insect-eaters.
The toad eats other things besides insects-he is seen at his best, perhaps, when battling with a huge and slippery angleworm, a delicacy that the horned lizard seems to scorn.
The lizard, on the other hand, is a star performer when placed on an anthill, or beside one of the numerous ant boulevards that can be found by the dozens along the edges of a path in any city park.
Here the ants go by in single file, and the horned lizard never misses one, the licking of his lips after each diminutive mouthful being his only relaxation in business-like activity.
When being kept as a pet, the toad needs a screened box half-filled with moist earth and bits of bark, under which he can retire on hot, or cold days, or after he has eaten to repletion.
The horned lizard needs some moisture, truly, but for a bed covering, he wants six inches of dry sand, into which he will dive head-first at the earliest approach of dusk, disappearing completely from view in two seconds' time, not to reappear again until the following morning when the sun has warmed the air sufficiently to suit reptilian requirements.