1 907.] OF CERTAIN SPECIES OF SQUAMATA. 41 



right lung, however, though there was a perfect agreement with 

 the left lung in the absence of any ventral cfecal outgrowths, such 

 as occur in other Ohamfeleons, there were three obvious cpeca at 

 posterior end. Milani figures five cseca. These were quite tubular 

 and not swollen at the free extremity, as, for instance, in Ch. 

 2X(jrvilobus. The walls are thick and they arise from a thick- 

 walled portion of the lung. These cseca are, in fact, exactly like 

 those of Ch. dilejns, from which the present species mainly difiers 

 in the extreme feAvness of the ca?ca, as is apparent from Milani's 

 figure. 



Chamceleon pumilus has lungs which differ in several important 

 points from those of the species that have been hitherto considered. 

 In the first place, there are no signs whatever of any bronchi in 

 the lungs. When the left lung is opened and the appearances 

 presented compared with those to be seen in Ch. vulgaris, the 

 following diflFerences are recognisable. In both the aperture of 

 communication between the two lungs, which represents, of course, 

 the distal extremity of the bronchus, permits the interior of the 

 right lung to be to some extent viewed. In the case of Ch. vul- 

 garis the cartilaginous rings of the bronchus have to be cut up 

 in order to display fully the aperture into the right lung through 

 which are seen the cartilaginous rings of the bronchus of the right 

 lung. In Ch. jnmdlus, when the lateral wall of the left lung is 

 removed no trace whatever of any bronchus is seen ; there is 

 simply a large circular orifice j)utting the two lungs into com- 

 munication, which shows no traces of any bronchial cartilages that 

 call be detected by the unaided eye. It is not plain whether this 

 condition is to be regarded as primitive or as evidence of degene- 

 ration. The lung itself is considerably shorter, relatively as well 

 as actually, than in the species which has been dealt with in the 

 preceding lines. It is, furthermore, different from the lungs of 

 these other species in that the typical lung-structure persists 

 throughout the whole sac. The alveoli in the lungs of Chamse- 

 leons generally are smaller and deeper proximally and get larger- 

 and shallower posteriorly, ultimately becoming pi-actically invisible. 

 The hinder region of the lung is anangious. In Chamceleon 2)umilus 

 the alveoli become rathei- less marked posteriorly, but they ai-e 

 much more conspicuously cii-cumscribed up to the very end of the 

 lung than is the case with any of the larger species which I have 

 had the opportunity of examining. The lung, in fact, is less 

 metamorphosed into a mere air- sac in the present species than in 

 any other which I have examined, excepting only Ch. tcenio- 

 hroiichus, to which species I shall have to refer again immediately. 

 In this particular it is plain that the lung of Ch. pamilus is moi-e 

 typically Lacertilian than that of such a species as Ch. vulgaris or 

 Ch. calcarifer. 



A final peculiarity shown by the lung of this species is very 

 remarkable. It has been stated in many general works that the 

 Chamseleons as a family are to be chai-acterised by the caecal out- 

 growths of the lungs, which have been considered in several 



