III. NOTES ON LACHES IS ANAMALLENSIS 

 AND ALLIED FORMS. 



By C. R. Narayan Rao, M.A., L.T., Mysore University, Bangalore. 



(Plate III). 



I had an opportunity to examine recently a small collection 

 of viperine snakes from Coorg and I noticed that the description 

 of Lachesis anamallensis given by Boulenger in his volume on 

 '' Batrachia and Reptilia " {Fatma of British India, p. 430) really 

 covers two distinct species. Obviously there is considerable 

 divergence of opinion in regard to the specific characters of 

 this viper. Major Wall gives sketches of it in his book on " The 

 Poisonous Snakes of India", which do not quite fit in with 

 Boulenger's description referred to above. For example, the 

 figures indicate only one postocular and eight upper labials, while 

 Boulenger makes out '* two or three small postoculars and nine 

 or ten upper labials." Moreover, Major Wall mentions (page 53) 

 that small scales may or may not be intercalated between the nasal 

 and the second labial, which fact is not noticed by any of the 

 early writers. 



Fayrer gives examples of specimens which differ from Giin- 

 ther's description of the scales oti the head and on the body of 

 T. anamallensis as being more or less distinctly keeled in twent}- 

 one rows {Thanatophidia , p. 20). Jerdon regarded {Journ. As. Soc. 

 Bengal, 1854, vol. XXII, p. 523) his Trigonocephalns malaharicus 

 as very closely allied to T. nigromarginatus, forms which have 

 since been considered identical respectively with T. anamallensis 

 and T. trigonophalus {Bonlenger , Faun. Brit. Ind., R:pt. and Bat., 

 pp. 430-431). It is also noteworthy that Giinthei calls attention 

 to Jerdon's reference to smooth scales in his description of Trigo- 

 nocephalus malabariciis and he maintains that ' ' they are keeled in 

 our species as in all Trimeresuri." Further he proceeds to men- 

 tion that "Mr. Elliot possesses a drawing of a young specimen, 

 named T. malabaricus (Jerd.). It resembles our species in colora- 

 tion, but has a white, black-edged temple-streak instead of a 

 black one. Mr. Jerdon does not mention either a black or a white 

 temple-streak" (Repl. Brit. Ind., p. 387). 



After examining the specimens in mj^ collection I cannot 

 resist the conclusion that these writers are really alluding to two 

 distinct species which in certain respects possess common charac- 

 ters, and Boulenger's description accordingly requires, in my 

 opinion, recasting; for his diagnosis of T. anamallensis is wide 



