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Show 1882.] DR. GADOW ON THE ANATOMY OF PTEROCLES. 327 II. Syrrhaptes paradoxus : 1st d. pancreat. inserted near the pylorus (%• 7). 2nd d. pancreat., -J-d. hepat. -f d. cystic. inserted opposite the pylorus. Pterocles arenarius (after Brandt) Syrrhaptes (after Brandt) Perdicula cambayensis ... Perdix cinerea Phasianus pictus swinhoei Euplocamus praalata Crax alberti Columba livia Peristera geoffroii Erythrcenas pulcherrima Total length of gut. centim. 83 80 87 38-42 75 106 106 122-152 222 96-125 125 34 41 Eelative length.1 7-8 6-7 8 7*5 7 7-7*5 9 12-13 10-11 4 55 Length of caecum. centim. 16 15*5 & 18-5 5 17 10-15 13 22&23 10&14 05-0-8 0 03 0 Distance of caeca from anus. centim. 15 12 13 3-4 6 8-12 7 8-12 15 4-5 4 The liver of the Rasores, as well as that of the Columbae, is quite different. The left lobe is divided again into two by a deep fissure, so that the whole organ might be called trilobed. The right lobe is generally the larger; a Spigelian lobe is present in most of these birds. The outline of the lower margin varies much in the different Fowls and Pigeons. The existence of a gall-bladder in the Pterocletes might be looked upon as a strong indication of difference between them and the Pigeons, as in the Gallinaceous birds this organ as a rule is well developed. However, it must not be forgotten that in several typical Rasores, as in Euplocamus, Numida, and Penelope, there is sometimes scarcely any pouch-like dilatation of the bile-ducts. In the Rasores the ca?ca are, without any exception, very well developed, and have mostly an extremely large and wide lumen. The length of both the ca?ca compared with the length of the intestinal tract (from pylorus to anus) is in the proportion of 1 ; 7 (Crax), or even 1 : 2*2 (Perdix). In the Pigeons, on the other hand, the cseca are always in a rudimentary condition, their sum total being in the proportion of 1 : 75 in our domestic Pigeon, and 1 : oo in Goura, Calcenas, Chalcophaps &c, as they are either completely wanting in most of the Columba?, or are only represented by very small, often barely visible, vermiform-like appendages. It has sometimes been stated that Pigeons have to rank with such birds as do possess ca?ca, because such organs, although very small, 1 See my paper in the 'Jenaische Zeitschrift fiir Naturwissenschaft,' 1879, p. 369. |