1\tEarthworm, c.s.
2\tMale ascarid C.s.
3\tFrog embryo, cleavage stage, sec.
4\tFrog blastula, sec.
5\tFrog gastrula, late stage, sec.
6\tFruitfly young w.m.
7\tFrog egg, one cell stage, sec.
8\tFrog egg, two cell stage, sec.
9\tFrog gastrula, early stage, sec.
10\tSimple flat epithelium, frog mesothelium, w.m.
11\tStratified flat epithelium, cat esophagus, w.m.
12\tHuman skin, sec. through hair follicle
13\tHuman skin, sec. through sweat glad
14\tDense connective tissue, rabbit Achilles tendon, sec.
15\tHuman blood, smear
16\tSkeletal muscle, dog diaphragm. L.s.c.s.
17\tTeased smooth muscle, frog, w.m.
18\tAnimal cardiac muscle sec.
19\tMotor neurons, ox w.m.
20\tSpinal cord, rabbit, c.s.
21\tMotor nerve endings, rabbit, w.m.
22\tWall of stomach, dog, sec.
23\tKidney, mice, l.s.
24\tArtery and vein, rabbit, c.s.
25\tSmall intestine, dog, sec.