SCINCID A. 131 
usually consist of a transverse one anastomosing with several longi- 
tudinal ones*. Head covered with symmetrical shields; an azygos 
occipital is rarely present. Pupil round. Eyelids well developed. 
No femoral pores. : 
Scincoids are cosmopolitan, the bulk occurring in Australia, the 
islands of the Pacific, the East Indies, and Africa; they are com- 
paratively very poorly represented in South America, Asfar as we 
know at present, all species are ovoviviparous. Adaptations to 
every mode of life, save aquatic and aerial, occur. 
I have met with great difficulty in arranging the genera of this 
family. The majority of the characters hitherto employed for 
the distinction of genera, such as the degree of development of the 
limbs, the presence or absence of a transparent disk in the lower 
eyelid, the presence or absence of keels on scales, &c., are in many 
cases not even of specific value; I have therefore used certain 
characters which hitherto have been neglected, but which, I am 
convinced, afford a firmer basis for a natural arrangement. The 
artificial nature of an arrangement based on the degree of develop- 
ment of the limbs has been pointed out by others?. In a family 
like the Scincoids, in which the limbs are undergoing a process 
of abortion, this character must be abandoned as one expressing 
relationship by itself; and I trust that the arrangement of the 
species in one or more series within a genus{, passing from forms 
with well-developed pentadactyle limbs and lacertiform physiognomy 
to such as have rudimentary limbs, or even none at all, marks 
a great improvement upon the artificial classifications in use down 
to the present day. 
\ 
Synopsis of the Genera. 
I. Nostril pierced in the nasal, or between nasal and supra- or post- 
nasal or first upper labial, not touching the rostral. 
A. Palatine bones separated on the median line of the palate 
(fig. a, p. 182) ; no supranasal shields. 
No azygos occipital shield ........ 1. Egernia, p. 134. 
An azygos occipital shield, in contact with the interparietal; tail 
prehensile .... ...ee sees sees 2, Corucia, p. 141. 
* Tho principal modifications of this structure have been exquisitely figured 
by Bocourt (Miss. Sc. Mex., Rept. pls. xxii. 7. & xxii.7.). Owing to the great 
amount of variation I have found within one and the same species, or difference 
between otherwise closely allied species, I have had to abandon the hope I 
at first entertained of employing this character for the arrangement of the 
enera in this family. 
- + Cf. Ginther, Eros: Zool. Soc. 1871, p. 243. i ; 
+ As examples of genera with several diverging degradational series, the 
genera Lygosoma and Chalcides are recomimended for study. r 
K 
