Vertebrata. Zoological Collections* III 



Although many varieties are met wdth in the distribution of the arteries 

 in birds, it may be stated, in general, that they occur less frequently than 

 in the mammalia. M. Cuvier, in his Anatomic Comparee, has insisted upon 

 the following differences as essentially distinguishing birds from mam- 

 malia : — 



1st, The division of the aorta into three principal branches, almost 

 immediately at its origin. 



2d, The division of the aorta at its abdominal extremity, where it has 

 no proper hypogastric and external iliac branches. 



3d, The arteries of the posterior (or abdominal) extremities do not pass 

 from a single branch analogous to the external iliac of mammalia ; but from 

 two arteries, which are detached successively from the aorta, at a great 

 distance from each other, and pass from the pelvis by two separate 

 apertures. 



4th, The absence of palmar and plantar arches. 



According to Dr Barkow, however, the 2d and 4th differences are unten- 

 able, because there are mammalia in which the abdominal aorta does not 

 divide into internal and external iliacs, and because there are birds v/hich 

 have a true plantar arch. 



But another difference, which might be added to those enumerated by 

 M. Cuvier, is, that the aorta passes before the right bronchus in birds, to 

 become the descending aorta, whilst in mammalia it passes before the left 

 bronchus (Meckel's ArchivJ) JBull. des Sci. Nat. xxii. 104. 



British Reptiles. — The natter-jack is admitted into the British Fauna 

 on the authority of a specimen said to have been taken on Putney Common, 

 by tlie late Sir Joseph Banks. Pennant's figure is copied from Roesel. It is 

 curious that no other English naturalist appears to have noticed the species, 

 for it is very common on many of the heaths in the south of England. More 

 than a hundred might be caught on a summer's evening on Blackheath, 

 Kent. I have often seen it on Clapham and Putney Commons ; and some 

 of my friends have found it in Cambridgeshire. It is well represented by 

 Roesel, whose figure has been copied by every succeeding author. It is 

 to be immediately distinguished from all the other B-ance by the yellow 

 dorsal line, and the red waits wdth which the body is thickly covered. Its 

 croak is very peculiar. 



On the other hand, the edible Frog (Rana esculenta,) has been admitted into 

 every work on British zoology, without the slightest hesitation ; and Dr 

 Fleming, in his compilation, observes, that it is " not so common as the pre- 

 ceding," (i. e. as the common frog, R. temporaria ; ) but, after the most careful 

 search, I have never been able to find it, or to get any account of it from 

 my friends, I have lately had an opportimity of observing the species on 

 the Continent, and of bringing some living specimens to London, and I am 

 perfectly satisfied that it is a distinct species. I am afraid, however, that 

 this species must be erased from our Fauna ; probably a variety of R. tern- 

 poraria has been taken for it. Indeed, the specific character given for R. 

 esculenta, in most Linnaean authors, is equally, if not more, applicable to that 

 species — J. E. Gray. , ir^KJjjivv j>aj j^u; . 



Figure of the Pupil in 5«a^e#. — Having lately kept the various species of 

 European snakes alive for some time, to observe the difference of colour that 

 they undergo during their growth, I was much struck by observing that all the 

 snakes ( Coluhri,) have orbicular central pupils, owing to the iris contract- 

 ing circularly ; while the adders or vipers ( Viperce,J have a linear perpen- 

 dicular pupil, extending right across the eye ; and, on examining such other 

 poisonous serpents as I could find alive in London, I observed that they 

 had the same conformation of the pupil as the Viperce^-^J. E. G. 



