CROCODILIANS, LIZARDS, AND SNAKES. 411 



Dr. Elliott Cones thus describes the habits of this species as observed 

 by him : ' 



Like other 8i>t>cies of the same gouus, this Phry)iosoma is slow of foot and readily 

 captured; it makes au interesting pet to one foiul of observing the traits of lower 

 animals. It may readily be secured by a thread tied behind its " horns," and in 

 this state of partial liberty its habits may be studied to advantage. It is one of the 

 most inort'ensive and amiable of reptiles, though some of the largest and boldest 

 individuals sometimes make a slight demonstration in self-defense by biting weakly. 

 It usually submits at once without remonstrance. When handled, it has a way of 

 making itself perfectly flat, when, closing its eyes, it will simulate death in this 

 collapsed state. Under some circumstances it will swell up the body prodigiously 

 till it assumes a nearly spherical shape. It has a sly way of watching for a chauce 

 to escape by bolting away when it thinks Itself unobserved, and a still nuire curious 

 knack of burying itself in sand or other loose soil. This is accomplished by a grad- 

 ual lateral and forward insinuating wriggling of the body, with the muzzle pointed 

 downward and the limbs drawn close to the sides. A few moments suffice for its 

 disajipearance. A certain slight means of defense which the "horns" may some- 

 times afi'ord is shown by the use they are pnt to wheu the animal is irritated by 

 poking with a finger or bit of a stick; then the head is lowered, the horns set for- 

 ward, the back arched up, and the whole attitude becomes ludicrously like that of 

 abull in miniainre. The horned lizards show special aversion to dogs. On approach 

 of one they raise themselves to the full length of the legs, puff out the body, open 

 the mouth, and hiss audibly, altogether presenting quite a formidable front. Their 

 food, iu confinement and otherwise, consists chiefly of flies and other insects, which 

 they capture by a quick thrust of the flesby tongue, lubricated with viscid saliva. 

 I have not observed the time of coition nor the period of gestation, but most of the 

 females are found pregnant in July, and the youug appear in great uumbers in 

 August. The male is usually smaller thau the female and of slenderer form. 



The varieties of this species have been distinguished by Girard as 

 species, and they have been thus defined by Stejneger:^ 



Size small ; horns rudimental; tail short; colors obscure P. d.doitglassii. 



Size larger; median horns directed posteriorly; tail longer; body more spinous; 



colors obscure P. d. Iteniandczii. 



Size largest ; median horns directed upward; colors more brilliant. . /'. d. ornatisvimum. 



An examination of a large series of specimens shows that the above 

 characters define races which do not seem to me to be sufficiently dis- 

 tinct to represent subspecies. Thus the direction of the occipital horns 

 is not constantly associated with other characters, and the length of 

 the tail of some specimens and of P. d. oniatissimnm is equal to that of 

 some individuals of P. d. hcrnandesL 



PHRYNOSOMA DOUGLASSII DOUGLASSII Bell. 



Pht-ynosoma douglassii douglassii Stk.jnkger, N. Amer. Fauna, No. 3, 1890, p. 112. 

 Phryuosoma douglassii var. /?. exilis Copk, Ann. Rept. U. S. Geol. Sur. Terrs., 



1871, p. 46. 

 Phrynosoma doiKjlassll Bell, var. Cope, Proc. Acad. Nat. Sci. Phila., 188.3, p. 20. 

 Phryno8oma douglassii pygmwa Yarrow, Proc. U. S. Nat. Mus., V, 1882, ]). 443. 



-A small form not more than one-half or two-thirds the usual size, but 

 nearly identical in details of structure and coloration, first described 

 from Carrington's Lake, Montana; Fort Hall, Idaho. The differences 



• Rept. U. S. G. G, Surv. W. of 100th Met., V, Zoology, p. 592. 

 2 North American Fauna, No. 3, 1890, p. 113. 



