XX INTRODUCTION. 



are tinctured with the most brilliant colours ; and as they 

 are called into the greatest activity in the bright sunshine, 

 nothing can surpass the splendour of their ever-changing hues. 

 Most of the Saurians are insectivorous ; but there are some, 

 as the Iguanas, which live principally on fruit. The activity 

 of the smaller insectivorous Lizards, when in pursuit of their 

 food is exceedingly curious and interesting. They watch 

 with all the caution of a cat, and dart upon their prey with 

 the quickness of lightning. 



In th'e act of seizing their food, however, they must neces- 

 sarily be exposed to some danger from the noxious qualities 

 of the insects which they indiscriminately attack. The fol- 

 lowing fact would seem to indicate that even in our own 

 temperate climate, an insect not generally recognized as poi- 

 sonous may inflict a fatal injury upon its Saurian enemy : 

 Some years since I had in my possession two living specimens 

 of the beautiful little green anolis of the West Indies, a 

 Lizard about the size of our own smallest species. I was in 

 the habit of feeding them with flies and other insects, and 

 having one day placed in the cage with them a very large 

 garden spider, Eptira diadena, one of the Lizards darted at 

 it, but seized it only by the leg. The spider instantly ran 

 round and round the creature's mouth, weaving a very thick 

 web around both jaws, and then gave it a severe bite in the 

 lip, just as this species of spider usually does with any large 

 insect which it has taken. The lizard was greatly distressed, 

 and I removed the spider, and rubbed off the web, the con- 

 finement of which appeared to give it great annoyance ; but 

 in a few days it died, though previously in as perfect health 

 as its companion, which lived for a long time afterwards. 



It has been already observed that the passage from the 

 Lizard tribe to the Serpents is by a succession of very gradual 

 modifications of developemeut. In the lower forms of the 

 Saurian group, the body becomes gradually elongated and 



