90 BULLETIN 151, UNITED STATES NATIONAL MUSEUM 



CHAMAELEON JACKSONl VAUERESCECAE Tornier 



Chamaeleon jacksoni var. vauerescecae Tornier, 1903, Zool. Jahrb. Syst., p. 176 

 (Forest at 7,000 feet at Nairobi, Kenya Colony). — Werner, 1911, Das 

 Tierreich. Chamaeleontidae, p. 26. — Loveridge, 1920, Proc. Zool. Soc. 

 London, p. 163 and 1923, p. 967 (Nairobi). 



Chamaeleon jacksoni Meek, 1910, Field Mus. Nat. Hist. Pub. 147, Zool. series, 

 vol. 7, p. 413 (Lukenya Province, Kenya Colony). 



3 (U.S.N.M. 40696-8) Meru, K. C. (Sm. Afr. Exped.) 1909. 



3 (U.S.N.M. 40977, 41678, 43054) Mt. Kenya, K. C. (Sm. Afr. Exped.) 



1909. 

 3 (U.S.N.M. 41797-9) Wambugu, K. C. (Sm. Afr. Exped.) 1909. 

 1 (U.S.N.M. 42489), Nairobi River, K. C. (Sm. Afr. Exped.) 1909. 



Chamaeleon jacksoni Boiilenger ^^ was described from a single half- 

 grown male collected by Sir F. J. Jackson in Uganda. It has since 

 been recorded from Meru by Lonnberg ^^ who has an excellent plate 

 of the 3-horned male and its hornless female. The race vauerescecae, 

 which Tornier described from the Nairobi forests, is characterized by 

 the female possessing horns like the male, though usually much 

 shorter, and frequently, though by no means invariably, the occipital 

 horns of these females are shorter than the rostral. Meek discusses 

 this point under the name of C. jacTcsoni though his specimens are 

 obviously of Tornier's race. 



The largest male (No. 40697) in the above series measures 238 

 (119 + 119) mm. Apparently all but two of the series are males; 

 certainly all 10 are horned, hence the reason for my emplojdng the 

 name vauerescecae for them. Six of the specimens, however, are very 

 young and of doubtful sex, though I should think that one (No. 41797) 

 is a female. The only adult female (No. 41678) was obtained on the 

 west side of Mount Kenya and carries 10 enlarged eggs; she measures 

 137 (73 + 64) mm. and has a 6 mm. -long rostral horn in process of 

 regeneration; the occipital horns are scarcely distinguishable as 

 minute spines not, or scarcely, larger than the adjacent scales. From 

 this one would conclude that Mount Kenya chameleons are referable 

 to the Nairobi race but on examining the series from Embu and Meru 

 in the Museum of Comparative Zoology I find that hornless and 

 horned females occur at both these places, which are not far distant 

 from Mount Kenya. It is undoubtedly true, however, that only 

 horned females occur at Nairobi, so that the almost topotypic speci- 

 men (male) from Nairobi River is undoubtedly of the vauerescecae 

 race. If it can be shown that there is a locality or region such as 

 Uganda in which only hornless females occur, then we must con- 

 sider Meru-Embu-Wambugu-Kenya zone as the meeting place where, 

 though the females may be arbitrarily sorted into jacTcsoni typica and 

 jacksoni vauerescecae, the males must remain intermediates. 



38 Boulcnger, 1896, Ann. Mag. Nat. Hist., ser. 6, vol. 17, p. 370. 



'» Lonnberg, 1911, Svenska Vetensk.-Akad. Hanrtl., vol. 47, p. 20, pi. 1, figs. 1 and 2 



