The genus Anniella was established by J. E. Gray[10], in 1852, to contain a single species which he named Anniella pulchra and described in the following terms:

"Silvery (in spirits); upper part with very narrow brown zigzag lines placed on the margin of the series of scales, the line down the center of the back and two or three on the upper part of the sides being thicker and nearly half the width of the scales.

Hab. California, J. O. Goodridge, Esq., Surgeon R. N."

This species has since been more completely described by Bocourt,[11] Boulenger,[12] Cope,[13] and Van Denburgh.[14]

In 1885 Fischer[15] described under the name Anniella nigra a specimen said to have been collected at San Diego, California. This, he stated, differed from Anniella pulchra in the following characters:

  1. Twenty-eight longitudinal rows of scales.
  2. The three median preanal scales twice as long as those preceding.
  3. Tail one-third total length.
  4. Color above black.

I have elsewhere[16] stated that the number of scale rows in Anniella pulchra varies from twenty-four to thirty-four. The preanal scales in both the dark and light forms may be small, moderately enlarged, or twice the length of those preceding. The tail of A. pulchra may equal or exceed one-third of the total length of the animal. I have been unable to discover any differences in the squamation of dark and light specimens; and since the recognition of A. nigra as distinct from A. pulchra must rest solely upon the difference in pigmentation, one is tempted to inquire whether this is not merely an instance of melanism. Upon this subject I shall have more to say, but I wish first to consider certain peculiarities of squamation which have been held to distinguish another species.

Anniella texana was described by Mr. Boulenger,[17] in 1887, from a single specimen labeled El Paso, Texas—a locality so far beyond the limits of the known range of the genus and of other Californian reptiles that it must be regarded with much suspicion until confirmed by the capture of additional specimens. The type of A. texana agrees in coloration with Anniella pulchra, but Mr. Boulenger finds it to differ in certain details of squamation. He assigns to it the following characters:

  1. Head less depressed, snout more rounded than in A. pulchra.
  2. A horizontal suture from nostril to second labial.
  3. Frontal twice as broad as long.
  4. Anterior supraocular nearly as broad as its distance from its fellow.
  5. Interparietal and occipital divided (anomalously?) by a longitudinal suture.
  6. Six upper labials, etc.
  7. A narrow shield separates the third labial from the loreal.
  8. Five lower labials.
  9. Twenty-eight scales around middle of body.
  10. No enlarged preanal scales.
  11. Tail ending obtusely, three-eighths total length.
  12. Dark gray above, with three fine black longitudinal lines; sides and lower surfaces whitish.