| OCR Text |
Show 516 MR. F. E. BEDDARD OX THE VASCULAR AND [May 1, the bronchus in each case being continued far into the interior of the lung as a gutter, which is, however, so narrow as not to be functionally a gutter at all; it is for the greater part merely a flat band composed of tracheal, or rather bronchial semirings. Relatively to the length of the two lungs, the bronchial rings extend perhaps nearly as far towards the posterior extremity of the lung in both cases. In the larger lung the bronchial semirings reach down a long way, nearly to the anangious part of that sac. They die away rather gradually, becoming narrower at the end of the series. It is also important to notice that the two bronchi do not diverge as they do in Python. In Boa the shorter bronchus does not arise by a perforation of the tracheal rings; but the aperture is seen to lie in a thickened area on one side of the bronchial rings appertaining to the right bronchus. The lungs of Boa constrictor present certain differences from those of B. diviniloqua. Milne-Edwards has mentioned the tracheal gutter in this species. The larger lung is vascular up to about the end of the first third of the liver. The bronchial gutter runs nearly as far as this point and ends rather abruptly; its rings do not decrease much in breadth towards their termination ; they do not fine off to a point. The smaller lung is vascular to a point about one inch beyond the commencement of the liver. It extends altogetlier about halfway down the liver. There is no trace of a bronchus belonging to this lung. It presents the appearance at its orifice of communication of being merely a lobe of the larger lung. It is clear that there is no orifice in the tracheal gutter such as is obvious in various Snakes which are provided with a second lung. But on a careful examination it may be seen that the edge of the tracheal gutter is slightly bitten out, as it were, for a space of a few lines where the smaller lung arises. There is no question of a bronchial gutter continued along this lung. (3) Notes upon the Boine genus Corallus. This snake is placed by systematists among the Snakes of the Boine division of the Boida?*. A dissection of the Madagascar species Corallus madagascariensis enables me to record certain anatomical facts which bear upon the question of its systematic placing, and which will also serve as a contribution to our knowledge of the anatomy of this division of Serpents. The example of this serpent which I dissected was not in a very favourable condition for unravelling the details of the circulatory system, for the veins, and, naturally, the arteries, were largely empty of blood, an anaemic condition which is not infrequent in reptiles that die in the Society's Gardens. Nevertheless, 1 have been able to ascertain a few facts about the veins which are of importance from the systematic standpoint. The first vein which I endeavoured to find was the umbilical. * Boulenger, Catalogue of Snakes in the British Museum, vol. i. p. 99. |
