250 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4ru Ser. 
be green, while the sides and tail are a beautiful bronze or yel- 
lowish brown. In some young specimens this bronze extends 
over the entire back. A few specimens have a second definite 
light line on the two outer rows of large dorsal scales. These 
lines may be yellow, a beautiful light green, or bronze. The 
lower surfaces are greenish white often becoming yellow on 
the limbs and tail. 
The differences between the lizards of the various islands 
may be summarized as follows: 
a.—Ventrals increased in number to more than six rows. No lateral light 
line. Dorsals tending toward reduction in number. 
i Miyako shima. 
a?—Ventral rows of large scales not more than six. A light lateral line. 
Dorsals tending toward an increase in number. 
b.—Usually two preanals. 
Okinawa shima. 
b?—Usually one preanal. 
c.—Rostral usually in contact with internasal. 
i Amami O shima. 
c?—Rostral usually not in contact with internasal. 
Kikaiga shima. 
Dr. Boulenger described the species from numerous speci- 
mens labeled merely Loo Choo Islands, but his statement that 
there are eight rows of large ventrals would incline one to 
believe that he must have had lizards from Miyako. He 
describes them, however, as having the pale yellow lateral 
lines. On the other hand Dr. Stejneger had a specimen from 
Miyako which he states has only six rows of ventrals. 
It seems, therefore, that we have here a single species occu- 
pying an extensive group of islands, and that upon each of 
these islands differentiation has begun but is still so slight 
as to be recognizable as an average difference only when large 
series are examined—the earliest tangible stage in the evolu- 
tion of new species. Corresponding with its greater geograph- 
ical separation, the lizards of Miyako seem to differ more from 
the lizards of the more northern islands than the latter do one 
from another. This probably indicates that Kikaiga shima, 
Amami O shima and Okinawa shima were united for some 
considerable time after their separation from Miyako shima. 
The question arises whether or not it is advisable to recog- 
nize in nomenclature such slight differences as occur in these 
lizards. Doubtless there is room for difference of opinion, 
