80 THE ZOOLOGIST. 



The Feeding Habits of Serpents. By Eaymond L. Ditmars. 

 Published at the Zoological Park, New York. 



This booklet forms a separate part of the publication known 

 as ' Zoologica,' consisting of contributions to the New York 

 Zoological Society, and is the result of a long study of the 

 feeding habits of these reptiles in captivity. The information 

 is of a most interesting and important character, and affords 

 support and also qualification to many zoological generalisations. 



The viperine poisonous snakes are for the most part short- 

 lived under observation, have an utter disinclination to feed, 

 while they " remain more timid than their innocuous allies, 

 which become readily accustomed to change of environment." 

 Another interesting conclusion relates to the Eegal Python 

 (Python reticulatus) from Malaysia. From repeated examina- 

 tions of the crates of newly arrived specimens of this species, 

 Mr. Ditmars is convinced that the big specimens, when in their 

 native environment, feed often upon the Indo-Malayan wild 

 swine. " Examination of the excreta in sixty per cent, of a 

 series of about forty specimens investigated showed liberal traces 

 of the bristles of Sus cristatus, and in numerous cases the horny 

 coverings of the feet." During recent years Mr. Ditmars and 

 his assistants have discovered that an annual fast of several 

 months' duration has increased the longevity of valuable reptiles 

 in this collection. "The writer is convinced that the impossi- 

 bility of keeping alive the big tropical vipers for more than a 

 3 T ear's time has resulted from feeding during a period when the 

 animal has secreted fatty sustenance to carry it past a period of 

 hibernation or aestivation, as the case may be." More startling 

 still is the recognition of the method by which reptiles may be 

 employed in economic agriculture. " Members of such genera 

 as Zamenis, Coluber, Pituophis, and Ophibolus may be regarded 

 as of marked economic value in the vast grain belts of the 

 United States, and their introduction into localities infested 

 with the smaller sciurine rodents is well worth serious trial and 

 extended observation. The species of Pituophis should be par- 

 ticularly useful owing to their strictly terrestrial habits and 

 inclination to prowl into the burrows of small mammals." 



This excellent publication is beautifully illustrated. 



