40 DR. MALCOLM SMITH ON 



alreaclj' mentioned in the footnote to M. achatina, tlie colouration and 

 degree of transparencj^ of M. ornata is bj' no means constant. 



Dimensions. Total length 28 mm., head and bod}' 9. 



The specimens examined were obtained at Nong Pling, near 

 Paknampo, in June. 



I could find no reliable character except that of size, upon 

 which to relj' for a diagnosis between these two species. Witii half 

 a dozen well grown living specimens of eacli in a dish together, it was 

 not difficult to separate them, clriefly on account of the difference in size. 

 Apart from this tlie snout of if. pulchra was shorter, the body less 

 regularly oval in sliape, and there was a partiuidar green tint about 

 the tadpole which made it easj' to distinguish it from M. ornata. On 

 none of these points however, could one rely, and in a preserved 

 specimen they would disappear entirely. 



The j'oung on leaving the water have the handsome markings 

 upon the back wliich are so characteristic of the adult. 



Callula pulchra. 



Head and body ; length about 1 i times its breadth ; much flat- 

 tened above ; snout very broad. Nostrils close together, much nearer 

 the eyes than the tip of the snout. Eyes perfectly lateral, six times as 

 far apart as the nostrils. Spiraculum median, large, the transparent 

 sheath opening below the hinder end of the body. Anal tube long, 

 median, curved downwards and backwards, projecting below the edge 

 of the caudal membrane. Tail twice as long as the head and body, 

 bluntly pointed ; crests full convex, about equal in depth. 



Mouth simple (without horny beak or teeth), very small, placed 

 at the extremity of the head, and consisting of a straight (viewed from 

 above) upper lip, and a contractile lower one. Toes not webbed. 



Colour. Dark olive-brown to black, with or without fine golden 

 speckles. Below often sjieckled with white. Sometimes a pale curved 

 bar across the snout, and light markings on the sides. Caudal mem- 

 branes colourless, or with small dark patches. 



Dimensions. Total length, 40 nun. Head and body, II. 

 Breadth of body, 9. Depth of tail, 7.5. 



It will be seen from the above description that this tadpole 



JOURX. NAT. HIST. SOC, SIAM. 



