162 REPTILES OF THE WORLD 



moss and rich soil. A specimen may suddenly emerge 

 from a damp spot, clean and shining, seemingly as im- 

 mime to a stain from the soil as is a duck's back to 

 water. 



In one part of the structure the Blind Worm is sin- 

 gularly interesting. The teeth are recurved, fang-like 

 and slioiv traces of a groove. Here are actually indica- 

 tions of, with time, the formation of a poisonous lizard. 

 The existence of such a character brings us directly to 

 the only known lizards that are venomous, two in num- 

 ber. 



The Beaded Lizards: Two strange American liz- 

 ards form the family Helodermatidce. In the ring-like 

 setting of their tubercular scalation they show their near 

 relationship to the Anguidce. They are very stout of 

 body with a short, fat tail. Above thejr are covered with 

 close-set, beady tubercles; beneath with flat plates or 

 scales. Their coloration is always vivid — pink and 

 black, or yellow and black, arranged in irregularly 

 blotched fashion on the bodj^ in broad rings on the tail. 

 The effect of the warty surface, together with the glar- 

 ing combination of colors is exactly like Indian bead- 

 work. 



From the character of the dentition, the present spe- 

 cies are unique among lizards. The teeth are recurved, 

 fang-like and swollen at the base; those on the lower 

 jaw are strongly grooved on both the front and the rear 

 surface. At the bases of these teeth is a chain of 

 glands containing a venom very similar in its composi- 

 tion to that secreted by the poisonous snakes, and suf- 

 ficiently powerful to produce death with man. 



The Beaded Lizards dwell only in desert places; one 

 in the United States and another in Mexico and Central 

 America. Between the two lies a great stretch of coun- 



