of snake poison, which is acid. It acts 

 upon the heart, the spine and the nerve 

 centers and causes paralysis. 



Other scientists claim the saliva of the 

 Heloderma is poisonous only in certain 

 cases and under certain circumstances. It 

 may also depend upon the physical condi- 

 tion of the victim at the time the venom 

 enters into the system. Yet there is lit- 

 tle doubt that, if help is not at hand im- 

 mediately, the bite may prove fatal. 



The Apaches stand in dire fear of this 

 animal, so that, at least, with their older 

 people no amount of money seems tempt- 

 ing enough to make them go near it, 

 much less to capture one. A former resi- 

 dent of the territories says both Indians 

 and Mexicans believe firmly that if a Gila 

 Monster only breathes in your face it is 

 quite sufficient to cause immediate death. 

 On an old Indian trail, a good day's jour- 

 ney west from the present site of Phoenix, 

 can be found, crudely outlined on the face 

 of a rock, the picture of two Helodermas 

 pursuing a man who runs to save his life. 

 Numerous hieroglyphic inscriptions tell 

 probably the story of the event and prove 

 not only the prehistoric origin of this 

 primitive piece of art, but also the errone- 

 ous ideas which were prevalent in these 

 remote times, for the reptile never attacks 

 and never pursues. It is safe to say that 

 the animal has been vastly misrepresented 

 at all ages. 



Nature has kindly provided the Helo- 

 derma with a compensation for its par- 

 tially undeserved bad reputation in giving 

 it beauty. For whosoever looks upon a 

 fine specimen with unprejudiced eyes can- 

 not fail to admire at least the combination 

 of its colors and especially the odd, ca- 

 priciously disposed markings; the deli- 

 cately tinted skin, studded in transverse 

 rows with shiny tubercles, like so many 

 beads on strings. 



The illustration to this paper is so ex- 

 cellently made that scarcely any descrip- 

 tion is necessary as to the animal's ex- 

 terior in color and markings. This Helo- 

 derma is a little over nineteen inches in 

 length by ten inches in circumference of 

 the body and five inches at the thickest 

 part of the tail, which makes one-third of 

 the total length of the body. When such 

 a reptile grows to the size of eighteen 

 inches it is called adult. Those growing 



beyond these figures are unusually large 

 specimens and in very rare instances the 

 species of our illustration reaches the ex- 

 traordinary length of two feet. An adult 

 Gila Monster weighs about two or three 

 pounds, and in winter less than in sum- 

 mer. 



The four short and stubby legs seem 

 quite out of proportion to the massive 

 body, much more so as the two pairs are 

 widely separated lengthwise of the body. 

 When walking the body is elevated, while 

 in rest it lies flat on the ground. Each 

 foot is provided with five digits armed 

 with curved white claws. 



The skin has generally the appearance 

 as if covered with rows of uniform beads ; 

 but, on closer examination, these beads, 

 or more correctly, tubercles, prove to 

 have different shapes and are differently 

 set, according to the part of the body 

 which they cover. On the head from the 

 nose up to between the eyes they are flat, 

 irregularly cut, closely joined and ad- 

 here completely to the skull. Those fol- 

 lowing form polygonal eminences, each 

 one separated from the other by a circle of 

 tiny dermal granulations, while behind 

 the eyes on both sides of the head they are 

 larger, semi-spherical and stand far apart. 

 The throat and the nape of the neck are 

 studded with very closely set small tuber- 

 cles, increasing in size only above the fore- 

 legs, whence they extend in well-defined, 

 transverse rows along the whole upper 

 side of the body and the tail. The under 

 side of the latter and the abdomen are 

 covered with tessellated scales of a light- 

 brown and dull yellow color arranged in 

 another handsome pattern. 



A Heloderma's head, with its triangular 

 shape, is very like that of a venomous 

 snake; it gives the animal — especially 

 when it is raised in anger — a truly awe- 

 inspiring appearance. 



The wide-cleft mouth reaches far be- 

 hind the eyes. These are very small and, 

 like all lizards, provided with eye-lids that 

 close when the animal sleeps. The eye 

 itself has a dark-brown iris, with the 

 round pupil that indicates diurnal or at 

 least semi-nocturnal habits. Between the 

 nostrils, well in front of the blunt nose, is 

 a wide space. The nostrils are so far down 

 as to nearly touch the margin of the su- 

 pra-labial scales. This position denotes 



