LIZAEDS. 319 



and it would appear that the different species intentionally keep 

 apart from each other. Colonel Tytler observes that "although 

 several species of geckos may inhabit the same locality, yet, as a 

 general rule, they keep separate and aloof from each other ; for in- 

 stance, in a house the dark cellars may be the resort of one species, 

 the roof of another, and crevices in the walls may be exclusively 

 occupied by a third species. However, at night they issue forth in 

 quest of insects, and may be found mixed up together in the same 

 spot; but on the slightest disturbance, or when they have done 

 feeding, they return hurriedly to their particular hiding-places." 116 

 Remarkable instances of broad specific range are presented by Hemi- 

 dactylus mabouia, which inhabits Brazil, San Domingo, Eastern 

 Africa, and Madagascar, and Gehyra mutilata, whose range extends 

 from the Mascarene Islands through India, the Malay Peninsula, 

 and New Guinea to Mexico. With the exception of the common 

 chamseleon (Chamseleo vulgaris), whose range extends from Anda- 

 lusia through North Africa eastward to India and Ceylon, all the 

 species of the family are restricted to the African continent and 

 the neighbouring islands (Madagascar, Bourbon, and Fernando 

 Po, the first with nearly one-half the total number of species). 

 The monitors, or water-lizards (Varanidse), which range over the 

 greater part of Africa, East India, Australia, and the Austro-Malay- 

 an islands, comprise the largest Old World members of the class, 

 some of the species measuring, or exceeding, six feet in length. 

 The common monitor of the Nile (Monitor Niloticus) is found in 

 the neighbourhood of all the more important streams of tropical 

 Africa. Psammosaurus scincus, a North African species, is strictly 

 terrestrial in its habits. 



The amphisbsenians, or footless lizards, which by Dr. Gray are 

 elevated to the rank of a distinct order, are principally tropical 

 American forms, although a considerable number of species are 

 known from the African continent, and a few, of the genus Blanus, 

 from the Mediterranean districts of Europe and Asia. In America 

 the species range from the Argentine Republic through the West 

 Indies to Florida (Rhineura [Lepidosternon] Floridana). Chirotes 

 lumbricoides, which is provided with the anterior pair of appen- 

 dages, is a Mexican species. A distinctively American family of 

 lizards is the Teiidse, or teguexins, which may be said to replace 

 the Old World Lacertidse, and whose range extends from Patagonia 



