. Animal physiology. Physiology, Comparative. 24:8 CHANGE OF CIRCULATION IN TADPOLE. its fisli-likc condition. At a is seen the large trunk which. issues from the ventricle, forming a bulbous enlargement like that which is seen in the corresponding part of the Fish. From this enlargement proceed three trunks on each side, called the branchial arteries {br^, br"^, br^), which convey the blood to the gills or branckice; and after being aerated bypassing through their filaments, the blood is collected by the bran- \ t 0 t 0 ab. vb '6 a ap av c ab 2 vb Fig. ]3G.—Blood-vessels of the Tadpole,
. Animal physiology. Physiology, Comparative. 24:8 CHANGE OF CIRCULATION IN TADPOLE. its fisli-likc condition. At a is seen the large trunk which. issues from the ventricle, forming a bulbous enlargement like that which is seen in the corresponding part of the Fish. From this enlargement proceed three trunks on each side, called the branchial arteries {br^, br"^, br^), which convey the blood to the gills or branckice; and after being aerated bypassing through their filaments, the blood is collected by the bran- \ t 0 t 0 ab. vb '6 a ap av c ab 2 vb Fig. ]3G.—Blood-vessels of the Tadpole, in first State. chial veins {vb, vb). Of these, the first pair transmits its blood by the vessels o, o, t, (which are also formed in part by the "econd pair) to the head and upper extremities; whilst the greater part of the blood of the second pair, with the whole of that of the third, is discharged into the trunlc c on either side. Ey the union of that vessel with its fellow, the trunk a vis formed ; which conveys the blood that has been aerated in the gills, to the general system, and is thus to be evidently regarded as the aorta. But we find here three small vessels (1, 2, and 3), which do not exist in the Fish; and which estabhsh a communication between the branchial arteries and the branchial veins, in such a manner, that the blood may pass from the former into the latter, mthout going through the filaments of the gills. These communicating vessels are very small in the Tadpole, and scarcely any blood passes through them ; but it is cliiefly by theij- enlargement, that the course of the blood is subsequently altered. There is also a fourth branch, 0/7, which proceeds to the limgs on either side; and as these organs are not yet developed, this pulmo- nary artery also is at first of very small size. 288. As the metamorphosis of the other parts proceeds,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for read
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Keywords: ., bookauthorcarpente, bookcentury1800, bookdecade1850, bookyear1859
