Holland, "Arboreal Tadpoles," Amer.
Tadpoles are aquatic vertebrates.
Some tadpoles reach a very great size.
Once there were eleven tadpoles in a glass globe set in a window full of plants.
In some Indian and Malay Engystomatids of the genera Callula and Microhyla, the tadpoles are remarkably transparent, and differ markedly in the structure of the buccal apparatus.
In others, which represent the perichordal type, the greater share of the formation of the whole vertebra falls to the (paired) dorsal cartilage, but there is in addition a narrow ventral or hypochordal cartilage which fuses with the dorsal or becomes connected with it by calcified tissue; the notochord is thus completely surrounded by a thick sheath in tadpoles with imperfectly developed limbs.
Tadpoles transported from one place to another.- Dendrobates, Phyllobates, Sooglossus.
In describing tadpoles, the term "body" is therefore used as meaning head and body.
In addition to these lines, all tadpoles show more or less distinctly a small whitish gland in the middle of the head between the eyes, the so-called frontal gland or pineal gland, which in early stages is connected with the brain.
The above description applies to all European and North American tadpoles, and to the great majority of those known from the tropics.
The creek flowed over a succession of rock ledges and formed pools at the edge where tadpoles swam.
This orifice is the spiraculum, which is lateral, on the left side of the body, in most tadpoles, but median, on the breast or belly, in those of the Discoglossidae and of some of the Engystomatidae.
Among European forms, some tadpoles of Pelobates attain a length of seven inches, the body being of the size of a hen's egg.