ORDER IV. The MEANTES, have both lungs and gills; and the feet are furnished with toes and claws.—This order contains but one genus, viz. the Siren. See SIREN.
The generic characters of this class are taken from the general figure of the body; from their having tails or no tails; being covered with a shell; having teeth, or no teeth, in the mouth; being furnished with wings; having covered or naked bodies; from the number, situation, and figure of the scuta and scales; from the number and situation of the spiracula; from the situation of the mouth, &c.
The specific characters are so very various, that it would be superfluous to enumerate them.
The Fourth Class, PISCES, is subdivided into four ORDERS, the characters of which are taken from the situation of the belly-fins.