350 Coe and Kunkel— California Limbless Lizard. 
latory system, the musculature, or the peripheral nerves. It is hoped, 
however, that the present series of studies may prove of interest 
because of their bearing on the evolution of this retrograde type of 
lizard and be of use in determining its systematic position. 
The genus Anniellu is apparently represented by a single known 
species (A. pulchra) described by Gray in 1852, although Boulenger 
(’87) briefly described a form said to have been collected in Texas 
(A. texana) which may possibly prove to be a distinct species. A. 
nigra, described by Fischer (’85) as a distinct species, is, as stated 
by Cope (:00, p. 675), merely a color variety of the common 
species. About two thirds of the individuals collected belong to 
this variety, the peculiarities of which are described below. 
The systematic position of the genus is to some extent a matter of 
discussion. Gray (’52) placed it among the Scincidze; Cope (’64) 
established for it a new family, Anniellidze, placing it in the tribe 
Typhlophthalmi ; Boulenger (’85) and Gill (’86) place the family 
Anniellide between the Anguide and the Helodermatide ; and 
Baur (’94) from a detailed study of the skeleton confirms Boulen- 
ger’s view. that the family is closely related to the Anguide, of 
which the common European limbless lizard, Anguzs, is the type. 
As will be seen from the account of the anatomical peculiarities 
given on the following pages, the evidence afforded by these investi- 
gations emphasizes the close relationship of the Anniellide and the 
Anguide. 
I.—Hasits anp VisceRaL Anatomy. W. R. Cor. 
Text-figs. 1-8. 
The natural history of Anniella is so imperfectly known that it 
seems desirable to give here such observations as we have been able 
to make on the habits of the animal. The brief observations in the 
field were supplemented by a study of some thirty animals which 
were kept alive for several months in the laboratory. 
The adult lizard is long, slender, and snake-like, averaging about 
170™™ in length when sexually mature, although there is great varia- 
tion in the length as compared to the diameter of the body because 
a considerable proportion of the individuals encountered have pre- 
viously lost a portion of the tail. After an injury of this sort the 
posterior extremity remains, at least for a long time, short, blunt, 
and rounded, while those animals which have not suffered such an 
injury have long and slender tails. 
