A REVISION OF THE LIZARDS OF THE GENUS 

 CTENOSAURA 



By John Wendell Bailey 



Professor of Biology, Mississippi College, Clinton, Miss. 



INTRODUCTION 



A few years ago Dr. Thomas Barbour, of the Museum of Com- 

 parative Zoology, in reporting on "Some Reptiles From Old Provi- 

 dence Island " ^ made the following statement concerning the genus 

 Ctenosaura: 



A single young Ctenosaura was obtained, which certainly is closely related to 

 C. completa Bocourt. It is, however, not improbably distinct and uudescribed. 

 The genus Ctenosaura, however, is in quite a chaotic condition, but it can not be 

 revised to meet the modern requirements of the discriminating systematist until 

 the types of the early authors can be examined; and in this case the types are 

 widely scattered in various European museums. 



Later Doctor Barbour took up the question of this genus with Dr. 

 L. Stejneger, curator of the division of herpetology at the United 

 States National Museum, receiving in response to his inquiries the 

 the following letter: 



Some time ago you asked my opinion as to Ctenosaura cycluroides and others 

 but frankly I am as much in a quandary as you. Many years ago I tried to get 

 light on the question, but gave up in despair, waiting till I should get more 

 material. In the course of time quite a number of specimens have accumulated, 

 of the group Boulenger calls C. acanthura, certainly over 150 — many very large 

 specimens, and of these many not too well preserved. However, I have not had 

 the courage to tackle them again. I had come to a tentative conclusion at the 

 time, based chiefly on the characters of the verticils of the tail, which seem more 

 reliable than those of the spines on the vertebral line, but I could not make up 

 my mind which was the real C. acanthura, which I think can only be ascertained 

 from an examination of the type in London. 



Shortly after the receipt of the above letter by Doctor Barbour 

 the writer matriculated in the graduate school at Harvard Univer- 

 sity, and immediately fell heii' to the "Ctenosaura problem," a task 

 that has been difficult and at times discouraging, yet very pleasant 

 because of the friendly interest manifested by coworkers in this 

 country and in Europe, 



'Barbour, T. Proc. New Engl. Zool. Club, vol. 7, pp. 81-85, May 6, 1921. 



No. 2733.— Proceedings U. S. National Museum, Vol. 73, Art. 12 

 88910—28 1 1 



