372 Coe and Kunkel— California Limbless Lizard. 
represented a much later period of embryonic life than did others, 
so that we have been able to follow the later development of the 
copulatory and other reproductive organs through their final stages 
of development and to compare them with the similar organs of the 
newly-born young and with those of the adult. We are therefore 
unable to give any account of the earlier stages of development 
either of the reproductive organs or of any of the organs of the 
body. 
The most striking feature of the well-advanced embryos is the 
possession of a pair of very conspicuous copulatory organs, which 
project from the sides of the cloacal opening and strongly resemble 
a pair of limbs. When most prominent these appendages project 
from the ventral side of the body for a distance fully one third as 
great as the diameter of the body itself in the same region. They 
are then gradually withdrawn into the cloacal aperture, and at the 
time of birth are fully concealed beneath the lips of this opening. 
Such appendages occurred in all embryos of a certain stage of 
development, and were apparently as conspicuous in females as in 
males. 
It was to study the structure and subsequent fate of these organs 
in both sexes that our studies were undertaken. This led naturally 
to an examination of the other reproductive organs of the adult 
animals, and in this connection a number of interesting peculiarities 
in which these lizards differ from others have been revealed. Some 
of these peculiarities are briefly described in two preliminary papers 
already published (Coe and Kunkel, :04 and :05), but are here 
given in greater detail. 
In the following account of the urogenital organs, including the 
peculiar structure of the two cloacal chambers and the copulatory 
organs, most of the details of structure will be omitted except where 
peculiarities are described which are different from those of the 
closely related European limbless lizard, Angu7s, and other lizards. 
For a general treatise on the anatomy of Anguis the reader is 
referred to the admirable accounts given by Leydig (772) and Braun 
CT). 
Testes and Sperm Ducts. 
As is the rule in the lizards and many other reptiles, the right 
genital gland is situated more anteriorly than the left, so that the 
right genital duct is the longer. In Anniella the right testis is 
usually about its own length in advance of the left (pl. xivz, fig. 38). 
