The small family of Lepidosternidæ has nearly the same distribution as the last, indicating a curious relationship between the Tropical parts of Africa and America. Lepidosternon and Cephalopeltis are American genera, while Monotrophis is African.

Family 30.—VARANIDÆ. (3 Genera, 30 Species.)

General Distribution.
Neotropical
Sub-regions.		Nearctic
Sub-regions.		Palæarctic
Sub-regions.		Ethiopian
Sub-regions.		Oriental
Sub-regions.		Australian
Sub-regions.
— — — —— — — —— 2 — —1. 2. 3 —1. 2. 3. 41. 2 — —

The Varanidæ, or Water Lizards, are most abundant in the Oriental region, whence they extend into the Austro-Malay Islands as far as New Guinea, and into Australia. Several species are found in Africa. Psammosaurus (1 sp.), is found in North Africa and North-western India; Monitor (18 sp.), has the range of the family; while Hydrosaurus (8 sp.) ranges from Siam to the Philippines, New Guinea, and Australia.

Family 31.—HELODERMIDÆ. (1 Genus, 1 Species.)

General Distribution.
Neotropical
Sub-regions.		Nearctic
Sub-regions.		Palæarctic
Sub-regions.		Ethiopian
Sub-regions.		Oriental
Sub-regions.		Australian
Sub-regions.
— — 3 —— — — —— — — —— — — —— — — —— — — —

The genus Heloderma, which constitutes this family, is found in Mexico.

Family 32.—TEIDÆ. (12 Genera, 74 Species.)

General Distribution.
Neotropical
Sub-regions.		Nearctic
Sub-regions.		Palæarctic
Sub-regions.		Ethiopian
Sub-regions.		Oriental
Sub-regions.		Australian
Sub-regions.
1. 2. 3. 41. 2. 3 —— — — —— — — —— — — —— — — —

The Teidæ, or Teguexins—a group of Lizards allied to the European Lacertidæ, but with differently formed superciliary scales—are highly characteristic of the Neotropical region, abounding almost everywhere from Patagonia to the Antilles and Mexico, and extending northwards to California on the west and to Pennsylvania on the east. The most extensive genus is Ameiva, containing nearly 60 species and having the range of the entire family; Teius (3 sp.), inhabits Brazil and Mendoza; Callopistes (2 sp.), Chili; Centropyx (3 sp.), Paraguay to Alabama; Dicrodon (Peru); Monoplocus (Western Ecuador); with Acrantus, Acanthopyga, Emminia, Crocodilurus, Custa, and Ada, which each consist of a single species, and all inhabit Tropical America.