152 Lens-Formation from Strange Ectoderm 
Fie. 1. Section through otic region of the operating stage, into which 
region the optic vesicle was transplanted. The rudiment of the otic vesicle 
is répresented by a thickening of the inner layer of the ectoderm. Beneath it 
lies mesoderm and then the thick wall of the pharynx. X 100 diameters. 
Fig. 2. Experiment DL,,. Optic vesicle transplanted caudal to the otic 
vesicle. Embryo killed 3 days after the operation. Section through the 
region of the transplanted eye showing medulla, chorda, myotomes, etc. As- 
sociated with the transplanted eye is a large lens-bud still attached to the 
inner layer of the ectoderm. It is 110 » in diameter and is as large as the 
normal lens but the latter has just separated from the ectoderm. The trans- 
planted eye is as large as the normal eye but somewhat irregular in shape. 
x 45 diameters. 
Fic. 3. Experiment DL,,. Section through edge of the above transplanted 
eye and lens-bud showing the attachment of the latter to the inner layer of 
the ectoderm. Compare with normal lens, Fig. 5. X 180 diameters. 
Fic. 4. Experiment DL,,. Section through about the center of the lens-bud 
of the transplanted eye showing small cavity and elongation of the cells in 
contact with retina. > 180 diameters. 
Fic. 5. Experiment DL,,. Section through center of normal lens. X 180 
diameters. 
Fic. 6. Experiment DL,.. Optic vesicle transplanted ventral to the otic 
vesicle. Embryo killed 3 days after the operation. Section through trans- 
planted eye and lens-bud, otic capsule (oc), medulla, and anterior myotomes. 
>< 45 diameters. 
Fic. 7. Experiment DL,,. Section through edge of transplanted eye and 
lens-bud showing its broad attachment and peculiar shape. The neighboring 
sections show a small cavity in the lens. The lens vesicle on the normal side 
is similar to that shown in Fig. 5. 180 diameters. 
Fic. 8. Experiment DL,. Optic vesicle transplanted ventral to otic 
vesicle. Embryo killed 3% days after the operation. Section through an- 
terior portion of irregular transplanted eye and lens showing medulla and 
ganglionic masses. This section is just anterior to the otic vesicle but the 
greater part of the transplanted eye lies ventral to it. X 45 diameters. 
Fic. 9. Experiment DL,,. Section through edge of above transplanted 
eye and lens-bud. The lens-bud is attached to the ectoderm and has a small 
irregular cavity. The lens-bud is much flattened and smaller than the normal 
one (see Fig. 10). ™X 180 diameters. 
Fic. 10. Experiment DL,,. Section through normal lens vesicle showing 
cavity filled with mass of degenerating cells. X 180 diameters. 
Fic. 11. Experiment DL,. Optic vesicle transplanted ventral to the otic 
vesicle. Embryo killed 3 days after the operation. Section through edge of 
the transplanted eye and lens showing attachment to the ectoderm. X 180 
diameters. 
Fic. 12. Experiment DL,. Section through same eye and lens a few sec- 
tions caudal to the above, showing irregular lens vesicle corresponding in 
shape to the eye cavity. This lens-bud is about the same size as the normal 
one, but the latter has separated from the ectoderm and is further differen- 
tiated (Fig. 13). > 200 diameters. 
